Unmanned aerial vehicle with collapsible net assembly

ABSTRACT

An example of a drone includes a drone chassis, a plurality of motors attached to the drone chassis and a plurality of propellers coupled to the plurality of motors. The drone further includes a net assembly mounted to the drone chassis. The net assembly extends above the plurality of propellers. The net assembly including a bottom portion and a plurality of upright frame members that are mounted to the bottom portion by a plurality of articulating joints.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. application Ser. No. ______,entitled “Unmanned Ariel Vehicle With Net Assembly” U.S. applicationSer. No. ______, entitled “Unmanned Ariel Vehicle With Latched NetAssembly” U.S. application Ser. No. ______, entitled “Unmanned ArielVehicle with Rotatable Net Assembly” all filed on the same day as thepresent application and which are hereby incorporated by reference intheir entirety.

BACKGROUND

Radio controlled unmanned aerial vehicles or UAVs (e.g. drones, such asquadcopters) can move at high speed and make rapid changes in directionwhen remotely piloted by a skilled user. A camera view from a drone maybe relayed to a user to allow a First Person View (FPV) so that the usercan see where the drone is going and steer it accordingly in the mannerof a pilot sitting in the cockpit of an aircraft.

A drone may include a flight controller that provides output to motorsand thus controls propeller speed to change thrust (e.g. in response tocommands received from a user via a communication channel such as aRadio Frequency (RF) communication channel established between a user'sremote-control and a drone). For example, a quadcopter has four motors,each coupled to a corresponding propeller above the motor, withpropellers mounted to generate thrust substantially in parallel (e.g.their axes of rotation may be substantially parallel). The flightcontroller may change speeds of the motors to change the orientation andvelocity of the drone and the propellers may remain in a fixedorientation with respect to the chassis of the quadcopter (i.e. withoutchanging the angle of thrust with respect to the quadcopter) and mayhave fixed-pitch (i.e. propeller pitch may not be adjustable like ahelicopter propeller so that each motor powers a correspondingfixed-pitch propeller in a fixed orientation with respect to a dronechassis).

SUMMARY OF THE DRAWINGS

FIG. 1 is an example of a counter-UAV drone.

FIG. 2 is simplified representation of some of the components for oneembodiment of a quadcopter.

FIG. 3 shows an example of some components of an autonomous quadcopter.

FIG. 4A-B show another example of a quadcopter.

FIGS. 5A-B illustrate interception of a target drone by a C-UAV.

FIG. 6 illustrates a method of operating a C-UAV.

FIGS. 7A-M illustrate aspects of examples of a C-UAV with a statictop-mount configuration.

FIGS. 8A-F illustrate aspects of examples of a C-UAV with entrapmenttop-mount configuration that includes a latch.

FIGS. 9A-H illustrate aspects of examples of a C-UAV with a rotatablenet assembly.

FIG. 10 illustrates a method of operating a C-UAV with a rotatable netassembly.

FIGS. 11A-J illustrate aspects of examples of a C-UAV with a collapsiblenet assembly.

FIG. 12 illustrates a method of operating a C-UAV with a collapsible netassembly.

FIG. 13 illustrates an example of components that may be used tointercept a target drone in a net assembly with moving parts.

DETAILED DESCRIPTION

The following presents systems and methods associated with UAVs ordrones. In an example, a counter-UAV drone (e.g. quadcopter) may beconfigured to intercept a target UAV in a safe manner (e.g. asubstantially non-destructive manner that does not result in the targetUAV being destroyed or falling to the ground).

In some situations, unidentified UAVs may be undesirable (e.g. forsecurity reasons). In situations where large crowds gather that may beterrorist targets, political events that include high profileindividuals that may be targets of assassination, no-fly areas nearairports or locations where emergency service aircraft need access (e.g.post-disaster areas), and militarily sensitive areas, unidentified UAVsmay be prohibited and some measures may be taken against anyunidentified UAVs that are observed. It may be desirable to disableand/or destroy any such unidentified UAV. In some situations, a targetUAV may be destroyed by gunfire, missile, or other highly destructivemethod. However, this may create a dangerous situation over inhabitedareas or crowds. Furthermore, in some cases it may be desirable to useless destructive techniques so that a target UAV may be recovered withlittle or no damage (e.g. to be used to investigate the source of theUAV, determine what technology is used in the UAV, and/or performreverse engineering to obtain the technology used). Therefore,destruction of unidentified UAVs is not always desirable and lessdestructive technologies may be preferable in some situations. Whileelectronic measures (e.g. jamming a signal from a remote-control to atarget UAV) may not be directly destructive, they may lead to a UAVcrashing and thereby may cause damage to the target UAV and/or to peopleand/or property on the ground.

In some examples of the present technology, a drone may be configured asa counter-UAV (C-UAV) drone that can intercept a target UAV and captureit in a non-destructive manner or in a manner that causes low levels ofdamage that leave the target drone substantially intact and avoid orreduce any potential impact on people and/or property on the ground.While some damage may occur to a target UAV resulting in some debrisfrom the UAV, the UAV and some or all debris may be captured to reduceor eliminate potential harm to people and/or property on the ground.

Aspects of the present technology may be implemented using a wide rangeof UAVs including, but not limited to drones (e.g. quadcopter drones).Such drones may be controlled by a user using a remote control and/ormay be controlled with little or no human input (e.g. using an autopilotto fly a predetermined flightpath and/or using Artificial Intelligence(AI) or other technology for autonomous flight).

Although the following description is primarily given the context ofdrones (e.g. quadcopters) moving along a three-dimensional flightpath tointercept and capture another drone moving along a three-dimensionalflightpath, certain concepts presented can be applied more generally.For example, the systems and techniques can be applied to non-droneaircraft and/or ground-based vehicles, watercraft and the like.

FIG. 1 shows an example of a counter-UAV drone 101 (C-UAV drone)intercepting a target UAV or target drone 103 (e.g. another drone thatis unwanted in the location where it is found and is therefore targetedfor interception). C-UAV drone 101 is controlled by remote control 105in this example. Remote control 105 includes a user input interface 107(e.g. one or more joysticks, buttons, touchpads, touchscreens,keyboards, or other input device(s) configured to receive a user'sinput). User input interface 107 allows a user to provide appropriateinput to control C-UAV drone 101 (e.g. by using joysticks to controldirection and speed of C-UAV drone). Remote control 105 also includes auser output interface 109 (e.g. one or more visual displays, lights,indicators, speakers, or other output devices configured to provideoutput to a user). For example, a display may show one or more viewsfrom camera(s) located on C-UAV drone 101 (e.g. a camera providing apilot's view from C-UAV drone 101 to allow FPV operation of C-UAV drone101). A C-UAV drone such as C-UAV drone 101 may be piloted (e.g. byremote control) to intercept a target drone (e.g. target drone 103) andcapture it in a non-destructive or low-destructive manner. In someexamples, a C-UAV drone may be configured for autonomous operation sothat some or all piloting is performed autonomously (e.g. without inputfrom a remote control such as remote control 105). For example, C-UAVdrone 101 may include one or more cameras (e.g. cameras that are pairedto form stereoscopic cameras) that may allow C-UAV drone 101 to locateand intercept target drone 103.

FIG. 2 is simplified representation of some of the components for oneexample of a drone 201, which is a remote-controlled quadcopter in thisexample. Drone 201 may be configured for as a C-UAV such as C-UAV drone101 according to some examples below. FIG. 2 shows flight controller 211connected to motors 217 a-d (which turn respective propellers, not shownin this view), the voltage source and regulator 213, wireless receiver215, video camera 231 and altitude sensor 233, and the transmitters 225and 227. In this embodiment, extending on an arm from each of thecorners of the drone is a motor 217 a-d, each of which is controlled bythe flight controller 211 to thereby control thrust generated bypropellers attached to motors 217 a-d. A voltage source (e.g. battery)and regulator 213 supplies power. A pilot's commands are transmittedfrom control signal transceivers such as cTx 223, received by wirelessreceiver 215. Control signal transceiver cTx 223 may be in aremote-control operated by a pilot (remote-control user) to fly drone201 The flight controller 211 uses power from the voltage source 213 todrive the motors 217 a-d according to the pilot's signals.

The drone also includes video camera 231 and altitude sensor 233 thatsupply data to the flight controller 211. An FM or other type videotransmitter 225 transmits data from the video camera 231 to a videomonitor receiver vRx 221 (external to the drone, such as on the ground)that monitors the video signals and passes on the video data to thepilot. Data can also be sent back to the control signal transceiver cTx223 by the transmitter 227. Although the transmitter 227 and wirelessreceiver 215 are shown as separate elements in FIG. 2, in manyembodiments these will be part of a single transceiver module. Andcontrol signal transceiver cTx 223 and video monitor receiver vRx 221may be part of a single transceiver module. For example, aremote-control, such as remote control 105, may include both a controlsignal transceiver and a video monitor receiver to allow aremote-control user to see video from video camera 231 while pilotingdrone 201.

FIG. 3 shows an example of an autonomous drone 301 (autonomousquadcopter in this example), which is different to drone 201 in that itis configured for autonomous operation, instead of, or in addition toreceiving commands from a remote user. Autonomous drone 301 may beconfigured as a C-UAV for intercepting target UAVs. For example,autonomous drone 301 may be configured to determine a flightpath tointercept the flightpath of a target UAV, and to adjust its flightpathas the target UAV changes direction, speed and/or orientation (e.g. inevasive maneuvers) without commands from a remote user. Instead ofreceiving commands via RF communication from a remote-control, when inautonomous mode, autonomous drone 301 may operate according to commandsgenerated by an Artificial Intelligence (AI) controller 330, which iscoupled to the flight controller 211 (components of autonomous drone 301that are common to drone 201 are similarly labeled). In thisarrangement, AI controller 330 selects a flightpath and generatescommands according to the same command set used by a remote-control.Thus, remote unit 332 may send commands to flight controller 211according to a predetermined command set when autonomous drone 301 is ina remote-control mode. AI controller 330 may send commands to flightcontroller 211 according to the same predetermined command set whenautonomous drone 301 is in an autonomous mode. In this way, flightcontroller 211 may operate similarly in both remote-control mode andautonomous modes and does not require reconfiguration (e.g. can changefrom remote-control to autonomous operation dynamically in-flight). Thisallows drones developed for remote-control to be easily adapted forautonomous operation, thus taking advantage of preexisting componentsand shortening development time for autonomous quadcopter development.In other examples, a flight controller and AI controller may be combinedin a single physical unit that is customized for autonomous flightcontrol.

In an example, AI controller 330 may be implemented in an AI module thatmay be considered as a bolt-on component that may be added to a fullyfunctional drone (e.g. instead of, or in addition to a remote-control).For example, AI controller 330 may be implemented by a controllermodule, such as an NVIDIA Jetson AGX Xavier module, which includes aCentral Processing Unit (CPU), Graphics Processing Unit (GPU), memory(e.g. volatile memory such as DRAM or SRAM), data storage (e.g.non-volatile data storage such as flash), and Vision accelerator. Othersuitable controller hardware may also be used. The AI controller 330 maybe connected to flight controller 211 and other quadcopter componentsthrough a physical connector to allow it to be connected/disconnectedfor configuration for AI control/remote-control. AI controller 330 maybe physically attached to autonomous drone 301 by being clipped on,bolted on, or otherwise attached (e.g. to the chassis of drone 301) in amanner that makes physical removal easy.

While a human pilot may fly a drone based on video sent to the pilotfrom the drone, an AI pilot, such as embodied in AI controller 330 maypilot a drone based on different input including sensor input and/orinput from multiple cameras (e.g. using Computer Vision (CV) to identifyand locate features in its environment including target UAVs). Whilehuman pilots may rely on a single camera to provide a single view (firstperson view, or “FPV”), an AI pilot may use a plurality of cameras thatcover different areas (e.g. a wider field of view, more than 180 degreesand as much as 360 degrees). In an example, cameras may be arranged inpairs, with a pair of cameras having overlapping fields of view. Thisallows such a pair of cameras to form a stereoscopic camera so thatdepth of field information may be extracted by a CV unit. FIG. 3illustrates an example of camera 334 a and camera 334 b, which arearranged with overlapping fields of view to form a stereoscopic camera334. Similarly, cameras 336 a and 336 b form stereoscopic camera 336 andcameras 338 a and 338 b form stereoscopic camera 338. It will beunderstood that the orientations (different angles corresponding todifferent views) and locations of cameras shown in FIG. 3 areillustrative and that the number, location, arrangement, and pairing ofsuch cameras may be varied according to requirements (e.g. more thanthree stereoscopic cameras may be used). In the example of FIG. 3, videooutputs of all cameras, 334 a, 334 b, 336 a, 336 b, 338 a, and 338 b(and any other cameras) are sent to AI controller 330. While one or morevideo output may be transmitted to an external location (e.g.transmitted by transmitter/receiver 340 to remote unit 332), in somecases no such transmission is performed when autonomous drone 301 is inautonomous mode. In some cases, an autonomous drone such as autonomousdrone 301 is configurable to receive commands from a remote-control suchas remote unit 332 (e.g. may be remote-controlled at certain times, e.g.according to selection by a remote user) through a communicationcircuit. These commands may use the same command set so that commandsfrom AI controller 330 and remote unit 332 are interchangeable.Transmitter/receiver 340 may be considered an example of a RadioFrequency (RF) communication circuit coupled to the flight controller211, the RF communication circuit (e.g. RF receiver) is configured toreceive external commands from a remote-control (e.g. remote unit 332)and provide the external commands to the flight controller 211 to directthe flight controller to follow a remotely-selected flightpath, theexternal commands and the commands provided by the AI controller 330from a common command set.

AI controller 330 includes computer vision (CV) capability to interpretinput from cameras 334 a, 334 b, 336 a, 336 b, 338 a, and 338 b to gaininformation about the environment around drone 301 (e.g. objectidentification and location that may be applied to target UAVs and/orother objects). Stereoscopic cameras 334, 336, 338 are configured toobtain different stereoscopic views to allow depth of field analysis sothat the proximity of objects (including target UAVs) may be accuratelydetermined. AI controller 330 may use CV capability to generate athree-dimensional (3-D) picture of the surrounding of autonomous drone301, or a portion of the surroundings (e.g. generally ahead ofautonomous drone 301 along its direction of travel). In some cases,multiple cameras may be used to collectively provide a full 360-degreefield of view. In other cases, cameras may cover less than 360 degreesbut may still collectively cover a larger field of view than a humanpilot could effectively monitor. Video output from cameras 334 a, 334 b,336 a, 336 b, 338 a, and 338 b may be directly provided to AI controller330 without conversion to RF and transmission as used byremote-controlled drones (e.g. remote-controlled quadcopters). This mayallow rapid reaction as drone 301 moves and video output reflectschanging surroundings (e.g. reduced latency may allow faster responsethan with remote-control).

AI controller 330 is coupled to the plurality of cameras 334 a, 334 b,336 a, 336 b, 338 a, and 338 b to receive input from the plurality ofcameras, determine a flightpath for the autonomous quadcopter (e.g.drone 301) according to the input from the plurality of cameras, andprovide commands to the flight controller 211 to direct the flightcontroller 211 to follow the flightpath. Thus, the role of flightcontroller 211 is to execute commands from AI controller 330 (as itwould from a remote-control user), while AI controller makes pilotingdecisions based on video input (and, in some cases, other input, e.g.from sensors). AI controller 330 may be considered an example of anArtificial Intelligence (AI) controller coupled to a plurality ofcameras (e.g. cameras 334, 336, 338) to receive input from the pluralityof cameras, determine a flightpath for the autonomous drone 301according to the input from the plurality of cameras, and providecommands to the flight controller 211 to direct the flight controller tofollow the flightpath. Flight controller 211 is coupled to the fourmotors 217 a-d to provide input to the four motors to control flight ofthe autonomous drone 301.

In addition to cameras 334 a, 334 b, 336 a, 336 b, 338 a, and 338 b,autonomous drone 301 includes Inertial Measurement Unit (IMU) sensors342 and rangefinder 344. IMU sensors 342 may measure one or more ofspecific force, angular rate, and magnetic field using a combination ofaccelerometers (acceleration sensors), gyroscopes (gyroscopic sensors),and magnetometers to generate motion data (e.g. autonomous quadcoptermotion data). For example, IMU sensors 342 may be used as a gyroscopeand accelerometer to obtain orientation and acceleration measurements.Rangefinder 344 (which may be considered a distance or range sensor)measures the distance from autonomous drone 301 to an external feature(e.g. the ground, obstacle or gate along a racecourse, target UAV,etc.). Rangefinder 344 may use a laser to determine distance (e.g.pulsed laser, or Light Detection and Ranging “LiDAR”). Outputs fromsensors 342 and 344 are provided to AI controller 330 in this example.Outputs from such sensors may also be provided to a flight controller(e.g. flight controller 211) in some cases. In addition to the sensorsillustrated, an autonomous drone may include other sensors such as abarometer, or altimeter, to determine height of a drone above ground,and/or LIDAR sensors using lasers to generate 3-D representations ofsurroundings. In some cases, a Global Positioning System (GPS) modulemay be provided to provide position information based on communicationwith GPS satellites.

AI controller 330 may be in the form of a removable module that is addedto a drone to provide capacity for autonomous operation. Within AIcontroller 330, certain modules may be provided with differentfunctions. In an example, different AI technologies may be comparedside-by-side by loading AI controllers with different AI code and flyingdrones using the different AI code (e.g. in a race) to compare AItechnologies. In such an example, certain basic functions of AIcontroller 330 may be provided by standard modules that are common tomultiple AI controllers while other functions may be customized by aparticular module, or modules, that are then compared by flying droneswith identical drone hardware, AI controller hardware, and someidentical modules within AI controllers provide a comparison of AItechnologies without effects of different hardware and/or softwaredifferences unrelated to AI piloting. Examples of autonomous drones,including autonomous quadcopters are described in U.S. patentapplication Ser. No. 16/360,999, filed on Mar. 21, 2019, which is herebyincorporated by reference in its entirety.

FIG. 4A shows a bottom-up view of an example of a drone 400, which maybe configured as a C-UAV that may be controlled by remote control and/ormay operate autonomously using CV and/or other systems. Drone 400includes cameras 412 a, 412 b, 414 a, 414 b, 416 a, 416 b mounted to theunderside of frame or chassis 402 (the term “chassis” is used to avoidconfusion with a frame used in a net assembly). In this examplepropellers 410 and 408 are protected by respective propeller guards(portions of chassis 402 that extend to protect propellers) so thatchassis 402 extends laterally beyond the propellers (unlike the examplesof FIGS. 2 and 3, which showed propellers extending beyond chassis). Theextent of 402 (beyond propellers) may facilitate configuration as aC-UAV drone in some examples. In other examples, a C-UAV drone may havea smaller chassis (e.g. as shown in FIGS. 2 and 3).

FIG. 4B shows another example of a quadcopter drone 440 that does notinclude propeller guards so that chassis 442 includes four separate arms442 a-d that extend from a central portion 442 e. Each arm 442 a-d has acorresponding motor 444 a-d mounted to it to turn a correspondingpropeller 446 a-d. Arms 442 a-d extend beyond propellers 446 a-d, whichmay facilitate implementation of some aspects of the present technology.

According to examples of the present technology, a drone such as aquadcopter may be equipped with one or more net to configure it as aC-UAV, with the net(s) configured to capture a target UAV while both theC-UAV and target UAV are flying. A C-UAV may be guided to intercept atarget UAV by a user via remote control (e.g. as illustrated in FIG. 1)and/or autonomously (e.g. using an AI controller and cameras).

When a C-UAV equipped with one or more net intercepts a target UAV, thenet(s) may engage the target UAV thereby preventing the target UAV fromflying away and thereby capturing the target UAV. For example, one ormore propellers of a target UAV may become entangled in portions of oneor more nets of the C-UAV. In an example, one or more nets may beconfigured for entanglement (e.g. by appropriate selection of dimensionsand material of strands, mesh spacing between strands, meshconfiguration and tension). In an example, one or more nets may form acage-like structure that may extend about a target UAV to form anenclosure to contain a target UAV and/or contain debris from a targetUAV (e.g. debris that may result from impact between portions of a netor C-UAV and/or from entanglement of spinning propellers with a net). Inan example, a combination of net(s) configured for entanglement andnet(s) configured to form an enclosure may be used together.

FIG. 5A illustrates an example of C-UAV drone 101 having a net assembly550 attached. C-UAV drone 101 is flown to intercept target drone 103. AC-UAV drone may be flown by a user via remote control 105 using one ormore cameras on C-UAV drone 101 and/or net assembly 550 (e.g. displayedon a screen of user output interface 109) to provide FPV and/or othervisual information to a user. The orientation of net assembly 550 whenapproaching target drone 103 may be controlled (e.g. using user inputinterface 107) to ensure entanglement and/or enclosure of target drone103 in net assembly 550 and to avoid collision between C-UAV drone 101and target drone 103. Alternatively, C-UAV drone 101 may operateautonomously to intercept target drone 103 (e.g. using CV technology to“see” and intercept target drone 103).

FIG. 5B shows C-UAV drone 101, net assembly 550 and target drone 103after interception of target drone 103. Target drone 103 is entangledand/or enclosed by elements of net assembly 550 so that it is no longerfree to continue independently along its own flightpath and is a captiveof C-UAV drone 101 (e.g. propellers of target drone 103 may be entangledso that they cannot turn and thus cannot generate thrust). In general,capturing a target drone in this manner changes flying characteristicsof C-UAV drone 101, which may be configured to rapidly adapt to such achange and continue flying while supporting the additional weight of atarget drone and adapting to the different center of mass and differentaerodynamic characteristics of the combined drones and net assembly.Configuration may include mechanical components to facilitateinterception and subsequent flight and electronic components (e.g. oneor more control circuits) that are configured to facilitate flight priorto, during, and after interception in a manner that allows rapidadaptation to the capture of a target drone so that stable flight ismaintained throughout.

Attachment of a net assembly such as net assembly 550 to a C-UAV dronesuch as C-UAV drone 101 may have various configurations and operation ofa net-equipped C-UAV may be adapted accordingly. In some examples, a netassembly may be passive, with no moving parts. In some examples, a netassembly may include dynamic components (e.g. electrical, mechanical,pneumatic, or other actuators) that facilitate entanglement and/orenclosure of a target drone.

A net assembly may include a frame to maintain netting in a desiredconfiguration during flight and during interception of a target drone. Aframe may be made of a lightweight material that is sufficiently strong(e.g. injection molded plastic, metal, carbon fiber, or other stronglightweight material). A variety of different net assemblies usingdifferent frames are described in the present disclosure. It will beunderstood that aspects of the present technology are applicable to arange of different net assemblies, using a range of different frames,nets and other components, and that the present disclosure is notlimited to any particular configuration or configurations of frame(s)and net(s).

A net assembly (e.g. net assembly 550) may be physically coupled to aC-UAV drone (e.g. C-UAV drone 101) using a quick-release mechanism. Thismay facilitate rapidly attaching and removing net assemblies from aC-UAV. For example, where multiple net assemblies are adapted fordifferent situations (e.g. for intercepting different types of targetdrones or operating in different weather or other conditions), aquick-release mechanism may allow rapid configuration of a C-UAV so thatit is rapidly launched with a desired configuration for a givensituation. A quick-release mechanism may also facilitate rapid removalof a net assembly that has been used for interception. For example, anet assembly that contains a target drone may be rapidly removed from aC-UAV, which may allow the C-UAV to be returned to service (e.g. withnew net assembly) and may allow a target drone to be removed to anotherlocation where it can be safely examined and/or destroyed. Aquick-release mechanism may be manually actuated (e.g. a hand-operatedclamping mechanism) or may be at least partially automated orremote-controlled. For example, actuated using an electro-mechanicalquick-release, which may release a net assembly from a C-UAV in responseto a command from a user (via remote control) or a command from softwarebased on some condition being met (e.g. the C-UAV and net assembly beingaway from people and/or property where dropping a net assembly haslittle or no risk of injuring people and/or property.

Attachment of a net assembly (e.g. net assembly 550) and C-UAV drone(e.g. C-UAV drone 101) may include one or more components configured tomanage the effects on the C-UAV of an impact with a target drone andsubsequent flying with the target drone in a net assembly. For example,some dampening and/or shock absorbing components may be included in aC-UAV and/or net assembly so that when a target drone impacts the netassembly, the shock of impact is not transmitted to the C-UAV in a waythat might cause damage (is dampened to reduce effects). Some physicalshock may be absorbed by appropriate components (e.g. using springs,cushions, elastic, and/or pneumatic components or other structures todampen impact and/or vibration) so that the risk of damage to thechassis or other parts of the C-UAV is reduced. After interception of atarget drone, a dampener may help to reduce shock and/or vibration froma captured target drone and thereby facilitate flying the C-UAV.

One or more strain gauge may be coupled to a net assembly and/or C-UAV(e.g. net assembly 550 and/or C-UAV drone 101) to measure strain of oneor more components during and after interception. This may allow a C-UAVto detect when a target drone has been captured (e.g. entangled and/orenclosed) and determine certain information regarding the capturedtarget drone (e.g. weight, location in a net assembly and drag as theC-UAV, net assembly and captured drone fly). This information may beused to modify flight so that it is adapted to the captured targetdrone. For example, information from one or more strain gauges may beprovided to control circuits (e.g. flight controller 211 and/or AIcontroller 330) that adapt flight control according to the informationreceived from strain gauges. Strain gauge information may also be sentto a remote control (e.g. remote control 105) so that a user may beprovided with information about the captured target drone. Strain gaugeinformation may be combined with other information (e.g. from one ormore cameras and/or other sensors) for flight control.

In addition to strain gauges, other sensors may be provided as part of anet assembly and/or C-UAV (e.g. net assembly 550 and/or C-UAV drone101). For example, optical sensors may be used to rapidly determine whena target drone is intercepted or is about to be intercepted. Forexample, one or more light source (e.g. Light Emitting Diode or LED) mayemit light that is received by one or more light detector (e.g. opticalsensors such as photodiodes) as long as the path between light sourceand detector is uninterrupted. In some cases, one or more reflectivesurfaces may be provided so that the light path between source anddetector may include one or more reflectors that change the direction ofthe light path. Using a system of one or more light sources, reflectors,and detectors allows a light curtain to be formed so that any objectpassing through the light curtain interrupts one or more light paths andis detected by at least one detector. The use of optical sensors mayallow the presence and/or location of a target drone near or within anet assembly to be detected so that C-UAV can adapt in real-time duringand after impact. Information from one or more optical sensors may beused to modify flight so that it is adapted to the captured targetdrone. For example, information from one or more optical sensors may beprovided to control circuits (e.g. flight controller 211 and/or AIcontroller 330) that adapt flight control according to the informationreceived from optical sensors. Optical sensor information may also besent to a remote control (e.g. remote control 105) so that a user may beprovided with information about the captured target drone. Opticalsensor information may be combined with other information (e.g. from oneor more strain gauges, cameras and/or other sensors) for flight control.

FIG. 6 illustrates a method of operating a C-UAV (e.g. C-UAV drone 101with net assembly 550) to safely intercept a target drone (e.g. targetdrone 103). This method and variations of this method may be used withnet assemblies as shown in the examples below or other net assemblies.The method includes piloting the C-UAV towards the target drone 660(e.g. by a user via remote control and/or autonomously using appropriatecontrol circuits). In some cases, this may be done by a user using oneor more cameras that provide FPV or other views. This may be assisted byother guidance (e.g. GPS, radar, lidar or other location or detectionsystem). In some cases, different systems may be used at different timesto guide a C-UAV towards a target drone. For example, a C-UAV may obtainan approximate location of a target drone and may use GPS to select aflightpath to the approximate location and may then proceed along theflightpath until it is at or near the approximate location. Then, theC-UAV may switch to visual or other systems that determine the locationof the target drone. For example, a camera may provide visualidentification of a target drone that allows the C-UAV to home in on thetarget drone. Similarly, radar, lidar, acoustic or other systems mayallow the C-UAV to locate the target drone once it is in range.Information from such systems may be provided to a user who pilots theC-UAV to intercept the target drone or the information may be sent to anAI controller that determines a flightpath to intercept the target droneor some combination of user input and AI input may pilot the C-UAV tointercept the target drone.

The method includes preparing to intercept the target drone 662 as theC-UAV approaches the target drone. For example, orientation of the C-UAVmay be adjusted to align a net assembly (e.g. net assembly 550) with thetarget drone prior to interception. In some cases, the net assembly maybe attached to the C-UAV in a manner that is rigid and not configurablein flight so that the C-UAV aligns the net assembly by changing itsorientation (e.g. by changing C-UAV orientation about the pitch, roll,and/or yaw axes). In some cases, the speed of the C-UAV may be changedprior to interception to a speed close to the speed of the target drone.In this way, the impact from intercepting the target drone may bereduced (i.e. a reduction in relative velocity may reduce impact). AC-UAV may move at a higher speed to get close to a target drone rapidlyand then move at a lower speed close to the target drone so that impactis reduced. The flightpath of the C-UAV may be changed according to theflightpath of the target drone so that the C-UAV maintains anintercepting trajectory even if the target drone changes course (e.g.attempts to evade capture).

The method includes detecting interception 664. This may includedetecting that a target drone has been entangled and/or enclosed in anet assembly using one or more of a camera, strain gauge, opticalsensor, or other sensor that provides an output indicating capture of atarget drone. For example, strain on net assembly or C-UAV componentsmay increase as a target drone is intercepted and is held in the netassembly. A strain gauge may detect such a change and may provide asignal to control circuits of the C-UAV accordingly.

The method includes determining information regarding the capturedtarget drone 666. For example, strain gauges, cameras, optical sensorsand/or other sensors may provide output that provides informationregarding the target drone. In addition to detecting the capture of atarget drone, appropriately located strain gauges may providequantitative information that allows the mass of a target drone to beestimated. The location of a target drone within a net assembly may alsobe determined (e.g. if captured target drone is on one side or in acorner of a net assembly, this may be indicated by different readingsfrom different strain gauges, different optical sensor outputs, and/orcamera outputs). Increased drag caused by a target drone may also bemeasured by strain gauges.

Information obtained in step 666 may be used in modifying flyingparameters according to information regarding the captured target droneto adapt flight 668. For example, the mass, location, and/or drag of acaptured target drone may be used by control circuits of the C-UAV toadjust operation of the C-UAV according to the information obtained. AC-UAV may adjust to the added mass from a captured target drone, forexample, by increasing power to motors according to the detected mass ofthe target drone so that additional thrust is generated to counteractthe weight of the target drone. A C-UAV may adjust according to thelocation of a captured drone, for example, by increasing power to motorson one side if the captured target drone is on that side. Where a netassembly extends horizontally from a C-UAV (e.g. in front) the addedmass of the captured target drone may provide a turning force that tendsto cause the C-UAV to increase pitch (pushing the front downwards).Power to front motors may be increased according to the mass andlocation of such a captured target drone to counteract the turning force(e.g. in proportion to the turning moment caused by the captured targetdrone). A C-UAV may adjust to increased drag caused by capture of atarget drone by increasing pitch and/or thrust according to theincreased drag to compensate for the increased drag and maintainairspeed.

Various configurations of net assemblies are described below. Any ofthese assemblies may be attached to a UAV (e.g. to drone 201, 301, 400)appropriately configured to form a C-UAV to intercept a target drone(e.g. as illustrated in FIGS. 5A-6).

Static Top Mount Configuration

FIG. 7A shows a first example of a C-UAV that includes UAV 770(configured as a C-UAV) with net assembly 772, which is mounted on topof UAV 770. UAV 770 (shown in side-view) includes legs 774 a-b (two offour legs are visible in this view) that are attached to the bottomsurface of chassis 776 and support chassis 776 when on the ground.Electric motors 778 a-b (two of four motors are visible in this view)are mounted to the top surface of chassis 776 and drive propellers 780a-b respectively. At the center of the top surface of chassis 776, aquick-release component 782 is coupled to a corresponding quick-releasecomponent 784 of net assembly 772 to allow rapid attachment anddetachment of UAV 770 and net assembly 772. A dampener 786 is coupledbetween quick-release component 784 and net assembly 772. Dampener 786is formed by four semicircular spring elements that provide flexibilityin the coupling between net assembly 772 and UAV 770. This flexiblecoupling may allow the angle of net assembly 772 with respect to UAV 770to change during and after impact. Thus, while net assembly 772 is shownparallel to chassis 776 of UAV 770, this may change when a target droneimpacts net assembly 772. In addition, elastic elements 790 a-b extendbetween net assembly 772 and chassis 776 of UAV 770. While two elasticelements are shown in this view, different numbers of elastic elementsmay be used. For example, four elastic elements may be provided,attached between corresponding corners of net assembly 772 and UAV 770.The combination of dampener 786 and elastic elements 790 may provideflexibility between net assembly 772 and UAV 770 so that the effects onUAV 770 of an impact of a target UAV and net assembly 772 is reduced(e.g. the shock of impact is substantially absorbed by dampener 786 andelastic elements 790). Vibration may also be substantially absorbed bydampener 786 and elastic elements 790. Sufficient clearance is providedbetween net assembly 772 and propellers 780 a-b to ensure that nocontact occurs between propellers 780 a-b and bottom portion 772 a ofnet assembly 772 even during impact. In some cases, elastic elements 790may be formed of suitable elastic material (e.g. molded plastic, rubber,synthetic rubber, or suitable elastomer) and configuration to haveelastic limits that ensure sufficient clearance (e.g. elastic limit ofat least one elastic element is reached before contact between bottomportion 772 a and propellers 780 a-b).

FIG. 7B illustrates a top-down view of fame elements of a bottom portion772 a (floor portion or floor) of net assembly 772 in relation to UAV770 showing how UAV chassis 776 and components of bottom portion 772 aare configured. In this view, it can be seen that UAV 770 is similar toquadcopter drone 440. UAV 770 includes UAV chassis 776 formed of arms776 a-d and central portion 776 e. Each arm 776 a-d has a correspondingmotor 778 a-d coupled to a corresponding propeller 780 a-d. Bottomportion 772 a is aligned with arms 776 a-d so that the corners of bottomportion 772 a are aligned with, and can be coupled to, arms 776 a-d byelastic elements 790 as previously shown (not shown in this view).Bottom portion 772 a includes a square formed of frame members 788 a-dwith two additional frame members, cross bars 791 a-b, forming anX-shape that overlies the X-shape formed by arms 776 a-d. At theintersection of cross bars 791 a-b, dampener 786 is attached to bottomportion 772 a. Dampener 786 is also attached, through a quick-releasemechanism (not shown in this view) to central portion 776 e of UAV 770.Bottom portion 772 a may include a net (e.g. a square panel of nettingmay extend throughout the square of bottom portion 772 a formed by framemembers 788 a-d). Such a net (or shroud) may be attached to framemembers 788 a-d around the perimeter of bottom portion 772 a to protectpropellers 780 a-d from damage (e.g. during and after impact of a targetdrone) by enclosing the captured target drone and preventing the targetdrone or fragments of the target drone from reaching propellers 780 a-dor other components of UAV 770. An example of suitable netting forbottom portion 772 a is formed of monofilament nylon strands that may beconfigured for protecting propellers 780 a-d using strands having arelatively large diameter (e.g. 1.5 mm) and may have relatively smallspacing (e.g. ¼ inch spacing) between strands. These strands may betightly strung nylon strands so that there is some tension on eachstrand and strands may cross at 90 degrees to form a pattern of squares(e.g. similar to a tennis racquet) or at some other angle to form apattern of diamonds.

While FIG. 7B shows bottom portion 772 a (floor) of net assembly 772that protects UAV 770, additional components of net assembly 772 extendupwards from this portion to enclose and/or entangle a target drone.Back, front and side portions of net assembly 772 may extend up from theperimeter of bottom portion 772 a to form an enclosure with the top open(or substantially open) to allow a target drone to enter. FIGS. 7A-Bshow the size of net assembly 772 being approximately the same as UAV770 (e.g. a two-foot-wide net assembly attached to a two-foot wide UAV)in some cases these dimensions may be different. In general, the size ofa net assembly may be selected according to a target drone size whilethe size of a UAV used with the net assembly may be selected to besufficient to fly with the net assembly both before and afterinterception (e.g. may be selected to have sufficient power to supportthe net assembly and a captured target drone).

FIG. 7C shows first side portion 772 b of net assembly 772 according toan example. First side portion 772 b extends up from bottom portion 772a along one side of net assembly 772. First side portion 772 b is formedby frame member 788 a, which is shared with bottom portion 772 a,upright frame members 788 e-f, top frame member 788 g, and nettingextending between frame members. These frame members (and all framemembers) may be formed of bars of a suitable material such as carbonfiber, injection molded plastic, metal, or other material and may haveany suitable shape (e.g. circular cross-section, I-beam, square,rectangular) and may be solid, hollow, or some combination of hollow andsolid. A second side portion may be substantially identical to firstside portion 772 b.

FIG. 7D shows first side portion 772 b (including netting) forming oneside of net assembly 772 and back portion 772 c (also includingnetting). Back portion 772 c includes frame member 788 b (shared withbottom portion 772 a) upright frame members 788 f, 788 h and top framemember 788 i. Bottom portion 772 a is shown without netting and withcross bars 791 a-b in outline for clarity. Netting is also omitted forclarity from front portion 772 d which includes frame member 788 d,upright frame members 788 e, 788 j and top frame member 788 k, and fromsecond side portion 772 e, which includes frame member 788 d, uprightframe members 788 j, 788 h, and top frame member 788 l. Bottom portion772 a, first side portion 772 b, second side portion 772 e, frontportion 772 d, and back portion 772 c form an enclosure that can enclosea target drone to prevent the target drone or portions of the targetdrone (e.g. fragments resulting from impact) from damaging the C-UAV orfalling to the ground. Top frame members 788 g, 788 i, 788 k and 7881form a rectangular opening that may allow a target drone to enter theenclosure. In some examples, the front, back, and sides may use similarenclosure netting to that used for the bottom portion as describedabove. In or examples, different netting may be used. For example,netting of first side portion 772 b, second side portion 772 e, frontportion 772 d, and back portion 772 c may use a smaller-diametermonofilament nylon strand with a larger spacing than that of bottomportion 772 a. In an example, netting of first side portion 772 b,second side portion 772 e, front portion 772 d, and back portion 772 cis formed of monofilament nylon strands having a diameter of 0.5 mm witha spacing of 2 inches between strands and with strands crossing at 90degrees to form a pattern of squares, or crossing obliquely to form apattern of diamonds. Netting of side portions may be consideredentanglement netting in some cases or as a hybrid between entanglementnetting and enclosure netting and may be configured accordingly.

It can be seen that frame members in FIG. 7D form a structure in theshape of a truncated wedge with front portion 772 d lower than the backportion 772 c, and with front portion 772 d inclined forward tofacilitate capture when net assembly travels in the forward direction(right to left in the view of FIG. 7D). In other examples, differentshaped enclosures may be used and the example of 7D is for illustration.For example, a net assembly may be triangular, circular or ellipticalinstead of substantially square in cross section along a horizontalplane. Upright frame members may extend at different angles than thoseshown. Curved frame members may be used instead of the straight framemembers illustrated.

In addition to the enclosure netting that forms the enclosureillustrated in FIG. 7D, entanglement netting may be provided so that atarget drone becomes entangled in the entanglement netting and thusbecomes captured by a net assembly. For example, entanglement nettingmay extend across the opening at the top of net assembly 772 or at somelevel between the top and bottom portion 772 a so that a target dronethat enters net assembly 772 tends to intersect the entanglement nettingwhen intercepted by a net assembly 772.

FIG. 7E shows entanglement netting 792 extending across the top openingformed by top frame members 788 g, 788 i, 788 k, 7881 (enclosure nettingof first side portion 772 b, second side portion 772 e, front portion772 d, and back portion 772 c are omitted for clarity of illustration).A light source 799 (e.g. LED) and a light sensor 793 (e.g. photodiode)are shown attached to top frame member 788 i. A reflector 797 is shownattached to top frame member 788 k to reflect light from light source799 back to light sensor 793. Interruption of this beam (indicated bydashed line), for example, when a target drone is entangled inentanglement netting 792, may be indicated by an output of light sensor793, which may be provided to control circuits of UAV 770 and/or to aremote control.

Entanglement netting may be similar to enclosure netting or may bedifferent so that it is better configured for entanglement of a targetdrone. For example, while enclosure netting may be tight (e.g. notsagging under its own weight and generally having some tension instrands that are stretched between frame members), entanglement nettingmay be loose (e.g. hanging down under its own weight and with strandsrelaxed and hanging from frame members instead of being stretchedbetween frame members). Entanglement netting may be formed of suitablematerial such as monofilament nylon strands with a diameter of 0.5 mmand a spacing of 4 inches. Strands may cross at 90 degrees to form apattern of squares or may cross obliquely to form a pattern of diamonds.

According to an aspect of the present technology, one or more straingauges may be placed along one or more frame members of a net assemblyto measure strain of frame members (e.g. during impact with a targetdrone). Such measurements may give an indication that a target drone hasbeen captured and may provide qualitative information about the targetdrone that may be used by the C-UAV drone and/or user.

FIG. 7F illustrates an example of strain gauges attached to andmeasuring strain in cross bars 791 a, 791 b. In this example, straingauges 792 a-b are attached to cross bar 791 a while strain gauges 792c-d are attached to cross bar 791 b. Strain gauges may be located atappropriate locations (e.g. half way between the center of bottomportion 772 a where cross bars 791 a and 790 b intersect and corners ofbottom portion 772 a). In other examples, more or fewer than four straingauges may be used (e.g. one strain gauge may be attached to each crossbar, or additional gauges may be attached). Strain gauges may beattached to other frame members such as frame members 788 a-d, uprightframe members, and/or top frame members (either instead of or inaddition to strain gauges attached to cross bars 791 a-b). Strain gaugesmay be coupled by wire to one or more circuits of a UAV (e.g. through aconnector that allows strain gauges to be connected rapidly anddisconnected rapidly).

FIG. 7F also shows a camera 796 mounted to top frame member 788 i toprovide a view of interception of a target drone as a C-UAV approachesthe target drone. Camera 795 may provide a video feed that is used by auser (FPV) to pilot a C-UAV so that net assembly 772 aligns with andimpacts the target drone (e.g. so that the target drone is captured inthe enclosure illustrated and becomes entangled in entanglement nettingthat may extend across the enclosure. By mounting camera 796 on netassembly 772 in this orientation, a pilot may use the video feed fromcamera 796 to align net assembly 772 with the target drone and adjust toany change in the target drone's flightpath. In another example, twosuch cameras may form a stereoscopic camera used with CV components toprovide target drone information to a processor (e.g. AI processor) forautonomous interception.

FIG. 7G shows some other locations for FPV cameras 798 a-c that may bealternative locations or additional locations (e.g. one camera may beplaced at one of the locations shown or more than one camera may beplaced at more than one of the locations shown). Cameras placed atmultiple locations may provide a stereoscopic view of a target dronebefore and during interception that may be used by a human pilot or AIpilot to guide net assembly 772 to interception the target drone. Insome cases, multiple camera views may be provided to a remote controlfor display at the same time to a user. In some cases, one camera viewmay be provided at a time with the camera view selected by a user asdesired (e.g. switching from a first camera used for takeoff and initialperiod of flight to a second camera used for interception, where thesecond camera may be mounted on a net assembly).

FIGS. 7H-J illustrate examples of how a net assembly such as netassembly 772 may be coupled to a UAV in a manner that provides dampeningof impact and/or vibration and allows quick attachment and detachment.Dampening is provided by dampener 786 in combination with elasticelements 790 b-c. FIG. 7H illustrates net assembly 772 separated fromUAV 770 with quick release component 784 exposed. In this example, quickrelease component 784 is a cylindrical portion of material (e.g.injection molded plastic) that fits in corresponding quick releasecomponent 782 on the top surface of UAV 770 when net assembly 772 iscoupled to UAV 770 (coupled by insertion of quick release component 784in corresponding quick release component 782 as indicated by arrows).

Quick release component 782 is shown in greater detail in FIG. 7I andincludes a flexible ring 782 a that is adapted to fit around quickrelease component 784 (i.e. has an inner diameter that in the openposition is greater than outer diameter of the cylinder of quick releasecomponent 784) to allow insertion. A cam lever 782 b allows the diameterof the flexible ring to be reduced so that quick release component 784is captured. Cam lever 782 may remain in the closed position until it ismanually flipped open to release quick release component 784 and thusallow separation of net assembly 772 from UAV 770. In an example, quickrelease component 782 and/or quick release component 784 include one ormore sensors to detect attachment/detachment of net assembly 772. Inaddition to the coupling shown, some electrical couplings may be madeusing one or more connectors. For example, one or more strain gauges,cameras, sensors, actuators and/or other electronic devices of netassembly 772 may be coupled to circuits of UAV 770 using connectors suchas JST connectors to allow rapid attachment and detachment.

FIG. 7H shows the location of dampener 786 and FIG. 7J shows dampener786 in more detail. It can be seen that, in this example, dampener 786includes four semi-circular springs 787 a-d that are coupled to quickrelease component 784 and also coupled to a cross-shaped portion 789with holes for cross bars 791 a-b that form the bottom portion of netassembly 772. The structure shown in FIG. 7J may be formed of a singlepiece of molded injection molded plastic for simplicity. An integrateddampener such as dampener 786 helps restrain vibratory motions likemechanical oscillations coming from capturing a target drone. Theintegrated dampener design has attributes including high damping andlarge range of elastic characteristics to absorb energy dissipated bythe captured target drone. Also, with its great energy dissipationcoefficient and flexibility on deformation amplitude, it reduces thenoise transferred unto the C-UAV which may impact the flight dynamicsduring steady flight and aggressive flight.

FIG. 7K illustrates dampener 786 in more detail. In this example,dampener 786 and quick release component 784 are formed of a singlepiece of material (e.g. injection molded plastic) and cross bar 791 a(which forms part of bottom portion 772 a) is inserted in a hole formedin the material (formed in cross-shaped portion 789). Thus, bottomportion 772 a is integrated with dampener 786 and quick releasecomponent 784.

One advantage of a quick release mechanism for a net assembly isinterchangeability of net assemblies and UAVs. For example, differentnet assemblies may be used with the same UAV (e.g. according to thetarget drone to be intercepted, according to weather conditions, orother external factors) and different UAVs may be used with the same netassembly.

FIG. 7L illustrates an example of net assembly 772 mounted to UAV 710,which is different to UAV 770. For example, UAV 710 includes motors andpropellers mounted on both an upper surface and lower surface of chassis712. Upper motors and propellers may be mounted to arms of chassis 710as shown in FIG. 7B with lower motors and propellers mounted below inthe same arrangement (e.g. at each point along a chassis arm where anupper motor is mounted to the upper surface a lower motor is mounted tothe lower surface). Lower propellers 714 a-b are shown below chassis 712(two additional lower propellers are not visible in this view). Legs 716a-b are sufficiently long to ensure some clearance between lowerpropellers 714 a-b and a landing surface when UAV 710 is at a landingpoint.

FIG. 7L shows a view from the front of net assembly 772 and UAV 710(i.e. with UAV 710 flying towards the viewer) showing cameras 798 a-cattached to net assembly 772 (and generally directed forwards along thedirection of travel. Additional cameras may be provided at additionallocations on net assembly 772 and/or UAV 710 as needed.

FIG. 7M shows a side-view of net assembly 772 and UAV 710 includinglower propellers 714 b and 714 c (which was hidden in FIG. 7L) andcameras 798 a-c.

An example of a drone includes a drone chassis; a plurality of motorsattached to the drone chassis; a plurality of propellers coupled to theplurality of motors, the plurality of propellers extending above thedrone chassis; and a net assembly mounted to the drone chassis, the netassembly extending above the plurality of propellers, the net assemblyincluding a frame and one or more portions of netting.

The net assembly may include a bottom portion, a first side portion, asecond side portion, a front portion, and a back portion each havingenclosure netting to form an enclosure. The bottom portion may includenetting formed of monofilament nylon strands of a first diameter havinga first spacing, the first side portion, the second side portion, thefront portion and the back portion may include netting formed ofmonofilament nylon strands of a second diameter that is less than thefirst diameter and have a second spacing that is greater than the firstspacing. The net assembly may further include an entanglement netextending across the enclosure, the entanglement net formed of strandsof monofilament nylon having a third spacing that is greater than thesecond spacing. The monofilament nylon strands of the bottom portion,the first side portion, the second side portion, the front portion andthe back portion may be tightly strung, and the monofilament nylonstrands of the entanglement net may be loosely strung. The drone mayinclude a quick-release mechanism coupling the net assembly to the dronechassis. The drone may include one or more strain gauges attached tomembers of the frame to measure strain of one or more frame members. Thedrone may include a dampener coupled to dampen shock or vibrationbetween the net assembly and the drone chassis. The drone may include aplurality of elastic elements coupled between the net assembly and thedrone chassis.

An example of a method of intercepting a target drone with acounter-unmanned aerial vehicle (C-UAV) drone includes: piloting theC-UAV drone towards the target drone; orienting the C-UAV drone to aligna net assembly mounted above propellers of the C-UAV drone with thetarget drone while flying towards the target drone; intercepting thetarget drone with the net assembly; detecting interception of the targetdrone; determining information regarding the target drone; and modifyingflying parameters of the C-UAV drone according to the informationregarding the target drone.

Intercepting the target drone may include entangling propellers of thetarget drone in an entanglement net of the net assembly. The netassembly may include one or more enclosure nets around the entanglementnet and intercepting the target drone may include enclosing the targetdrone within the enclosure nets to prevent contact between the targetdrone and propellers of the C-UAV drone. The net assembly may includeone or more strain gauges and detecting interception of the target dronemay include detecting changes in output of the one or more straingauges. The method of may further include subsequently piloting theC-UAV drone with the target drone to a landing point and detaching thenet assembly with the captured target drone from the C-UAV using aquick-release mechanism. The net assembly may include a camera andorienting the C-UAV drone to align the net assembly with the targetdrone may include using a First-Person View (FPV) provided by thecamera.

An example of a Counter-Unmanned Aerial Vehicle (C-UAV) quadcopterincludes: a quadcopter chassis; a first motor, a second motor, a thirdmotor, and a fourth motor attached to the quadcopter chassis; a firstpropeller, a second propeller, a third propeller, and a fourth propellercoupled to the respective first, second, third, and fourth motors abovethe quadcopter chassis; and a net assembly mounted to the quadcopterchassis by a quick-release mechanism, the net assembly extending abovethe first, second, third, and fourth propellers, the net assemblyincluding an entanglement net to entangle a target drone and anenclosure about the entanglement net to protect the first, second,third, and fourth propellers from the target drone.

The C-UAV quadcopter may include a plurality of strain gauges attachedto components of the net assembly to detect presence of the target dronein the net assembly. The C-UAV quadcopter of may include one or morecameras mounted to the net assembly. The C-UAV quadcopter may includecontrol circuits configured to receive outputs of the plurality ofstrain gauges and outputs of the one or more cameras and to adjustflying parameters of the C-UAV quadcopter in response to the outputs.The entanglement net may be formed of loosely strung nylon strandshaving a wide spacing and the enclosure may be formed by tightly strungnylon strands that having a narrow spacing.

Entrapment Top-Mount Configuration

While the above Figures show particular examples of a top-mount netassembly (a net assembly configured to be mounted above the chassis andpropellers of a UAV), aspects of the present technology are applicableto other net assemblies including top-mounted net assemblies that may bedifferently configured. Some examples may include only static or passivecomponents (e.g. a frame and net) while other examples may include oneor more dynamic components that are actuated in some manner duringinterception of a target drone to entrap or enclose the target drone.

FIG. 8A shows an example of a top-mounted net assembly 802 that may bemounted to a UAV configured for C-UAV operation (e.g. UAV 770 or UAV710, not shown in FIG. 8A) so that it extends above propellers of theUAV (e.g. in a manner similar to net assembly 722 and UAV 770). Netassembly 802 includes a bottom portion 802 a (floor) that is similar tobottom portion 772 a as previously shown and may include frame membersforming a square with cross bars between corners of the square in an Xconfiguration (e.g. as shown in FIG. 7B). One or more strain gauges maybe attached to cross bars of bottom portion 802 a (e.g. as illustratedin FIG. 7F) and/or other frame members of net assembly 802. Bottomportion 802 a may be similarly aligned with a UAV and may be similarlyattached using a dampener (e.g. like dampener 786), elastic elements,and a quick release component (like quick release component 784) asillustrated in FIGS. 7H-I. Net assembly 802 is generally symmetric fromfront to back and from side to side so that (unlike net assembly 722)the front, back, and side portions are similar in size and shape. Inaddition to upright frame members and top frame members (which may besimilar to those of net assembly 772) net assembly 802 includesintermediate frame members that form a frame 804 parallel to bottomportion 802 a. An entanglement net (not visible in FIG. 8A) may beattached to frame 804 so that it extends across net assembly 802 at anintermediate height (e.g. about halfway between bottom portion 802 a andthe top of net assembly 802.

FIG. 8A also shows a hinged portion or latch 806 (catcher) in an openposition in which it extends upwards from net assembly 802. Thispresents a large area to a target drone being intercepted so that theprobability of interception is high. Latch 806 may be formed of a singleframe member with an opening that has netting extending across it. Theframe member may be formed of similar material to other frame members(e.g. carbon fiber, plastic, or metal).

FIG. 8B shows another view of net assembly 802 with latch 806 in theopen position. FIG. 8B shows enclosure netting along sides of netassembly 802 (e.g. stretched across frame members to form front, back,and side portions of net assembly 802). Entanglement net 810 can be seenextending across frame 804 at an intermediate height. Net 807 of latch806 may be similar to one or more other nets described above. Forexample, net 807 may be an entanglement net that is similar toentanglement net 792 described above (e.g. both entanglement nets 810and 807 may be formed of strands of monofilament nylon) so that a targetdrone colliding with latch 806 becomes entangled in net 807.

FIG. 8C shows a detailed view of a portion of net assembly 802 includinghinge mechanism 812 coupling latch 806 to the frame of net assembly 802so that it can rotate between the open position shown and a closedposition. In some examples, hinge mechanism is a passive mechanism (e.g.a simple hinge) so that latch 806 may move from the open position to theclosed position as a result of impact with a target drone and/or theresulting weight of the target drone when it becomes entangled in net807. In other examples, a hinge mechanism such as hinge mechanism 812may be actuated to close (e.g. may be spring loaded, pneumaticallyactuated, electrically actuated, or otherwise moved by some mechanicalforce). A hinged portion or latch may be spring loaded and latched sothat it is unlatched by collision of the target drone and the hingedportion closes or folds down on a target drone (e.g. it may snap closedin the manner of a mouse trap). A closing mechanism (e.g. pneumatic orelectromechanical mechanism) may be actuated in response to a signal,for example, a signal from a sensor and/or control circuits, where thesignal is generated in response to detection of impact of latch 806 witha target drone. Such a signal may be generated by control circuits of aUAV (e.g. UAV 770), which may generate the signal in response to inputfrom one or more strain gauges, cameras, optical sensors, and/or othersensors. Latch 806 may latch closed (e.g. there may be some mechanism toprevent latch 806 from opening without manual intervention so that itremains closed until it reaches a landing point) and a sensor may detectwhen it is in the closed or open position so that this information isprovided to a user and/or AI circuits.

FIG. 8D illustrates net assembly 802 with latch 806 in the closedposition lying parallel to bottom portion 802 a and frame 804. Latch 806may lie on frame 804 and/or net 810 that extends across frame 804. Thus,when latch 806 closes with a target drone entangled in net 807, thetarget drone may become further entangled in net 810 and may be enclosedby sides of net assembly 802 and between net 810 below and net 807 oflatch 806 above to reduce the probability that the target drone, orfragments of the target drone, could escape and cause damage.

FIG. 8D also shows an example of a camera 814 attached to net assembly802 to provide FPV flying capability to facilitate capture of a targetdrone by net assembly 802 attached to a UAV. Camera 814 may look throughnet 807 when latch 806 is in the open position to facilitate alignmentof latch 806 with a target drone. A camera may be mounted at one or morealternative or additional locations (e.g. at the front of net assembly802 where reflector 818 is located and/or on bottom portion 802 a.

FIG. 8D also shows light source 816 (e.g. LED) generating a light beam817 which extends to reflector 818 and is reflected back to light sensor820 (e.g. photodiode). Interruption of beam 817 may occur when a targetdrone blocks beam 817 (e.g. when entangled in net 807 and/orentanglement net 810 and this interruption be indicated by an output oflight sensor 820, which may be provided to control circuits of UAV 770and/or to a remote control. In another example, latch 806 may include areflector so that a target drone impacting latch 806 blocks a beam,which is detected by and optical sensor (light sensor 820) and inresponse, control circuits may trigger closing of latch 806 by anactuator.

FIG. 8E shows net assembly 802 attached to UAV 710 from the front,including latch 806 in the open position so that net 807 is exposed andis likely to catch a target drone. Camera 814 and camera 824 (mounted tothe back of bottom portion 802 a) look forward (towards the viewer inthis perspective) so that they can be used to guide UAV 710 and netassembly 802 to intercept a target drone and/or provide informationabout a target drone that may be used to modify flying parameters of theC-UAV. While not shown in FIG. 8E, elastic elements (e.g. similar toelastic elements 790 a-b of FIG. 7A) may extend between corners ofbottom portion 802 a and arms of UAV 710. In some cases, a latch such aslatch 806 may be removable so that a net assembly can be converted froma dynamic configuration (e.g. as shown in FIG. 8E) to a staticconfiguration that does not have a latch. For example, a latch may beadded to net assembly 772 described above to change its configuration toa dynamic configuration.

FIG. 8F illustrates an example of a method of using a C-UAV configuredwith a net assembly that includes a latch (e.g. net assembly 802 withlatch 806 as shown in FIG. 8E). The method includes piloting the C-UAVdrone towards the target drone 831, orienting the C-UAV drone to align anet assembly mounted above the C-UAV drone with the target drone whileflying towards the target drone 833, and intercepting the target dronewith the net assembly including moving a hinged portion (e.g. latch) ofthe net assembly from an open position extending upwards from the netassembly to a closed position overlying the target drone 835. The methodfurther includes detecting interception of the target drone 837,determining information regarding the target drone 839 (e.g. weight) andmodifying flying parameters of the C-UAV drone according to theinformation regarding the target drone 841.

An example of a drone includes: a drone chassis; a plurality of motorsattached to the drone chassis; a plurality of propellers coupled to theplurality of motors; and a net assembly mounted above the drone chassis,the net assembly including an enclosure and a hinged portion thatextends upwards from the enclosure in an open position and folds down ina closed position.

The drone hinged portion (latch) may include netting configured toentangle a target drone. The drone may include an entanglement netextending across the enclosure. The enclosure may include a bottomportion, a first side portion, a second side portion, a front portion,and a back portion each having enclosure netting attached to framemembers. The bottom portion may include netting formed of monofilamentnylon strands of a first diameter having a first spacing, the first sideportion, the second side portion, the front portion and the back portionmay include netting formed of monofilament nylon strands of a seconddiameter that is less than the first diameter and have a second spacingthat is greater than the first spacing. The net assembly may include afirst entanglement net extending across the enclosure and a secondentanglement net extending across the hinged portion, the first andsecond entanglement nets formed of strands of monofilament nylon havinga third spacing that is greater than the second spacing. Themonofilament nylon strands of the bottom portion, the first sideportion, the second side portion, the front portion and the back portionmay be tightly strung and the monofilament nylon strands of the firstand second entanglement nets may be loosely strung. The drone mayinclude a quick-release mechanism coupling the net assembly to the dronechassis. The drone may include one or more strain gauges attached to oneor more frame members of a frame of the net assembly to measure strainof the one or more frame members. The drone may include a dampenercoupled to dampen shock or vibration between the net assembly and thedrone chassis. The drone may include a plurality of elastic elementscoupled between the net assembly and the drone chassis.

An example of a method of intercepting a target drone with acounter-unmanned aerial vehicle (C-UAV) drone includes: piloting theC-UAV drone towards the target drone; orienting the C-UAV drone to aligna net assembly mounted above the C-UAV drone with the target drone whileflying towards the target drone; and intercepting the target drone withthe net assembly including moving a hinged portion of the net assemblyfrom an open position extending upwards from the net assembly to aclosed position overlying the target drone.

The may include: detecting interception of the target drone; determininginformation regarding the target drone; and modifying flying parametersof the C-UAV drone according to the information regarding the targetdrone. The hinged portion may be coupled to an actuator configured tomove the hinged portion from the open position to the closed position inresponse to detecting interception of the target drone. The hingedportion may be configured to move from the open position to the closedposition using at least one of: weight of the target drone and a latchedspring that is unlatched by collision of the target drone and the hingedportion. Intercepting the target drone may include entangling propellersof the target drone in an entanglement net of the hinged portion. Thenet assembly may include one or more: strain gauges, cameras, andoptical sensors.

An example of a Counter-Unmanned Aerial Vehicle (C-UAV) quadcopterincludes: a quadcopter chassis; a first motor, a second motor, a thirdmotor, and a fourth motor attached to the quadcopter chassis; a firstpropeller, a second propeller, a third propeller, and a fourth propellercoupled to the respective first, second, third, and fourth motors; and anet assembly mounted to the quadcopter chassis by a quick-releasemechanism, the net assembly extending above the first, second, third,and fourth propellers, the net assembly including an enclosure and ahinged portion, the hinged portion configured to intercept a targetdrone in an open position and overly the target drone within theenclosure in a closed position.

The C-UAV quadcopter may include: a plurality of strain gauges oroptical sensors attached to components of the net assembly to detectpresence of the target drone in the net assembly; and one or morecameras mounted to the net assembly for First Person View (FPV)operation of the C-UAV quadcopter for intercepting the target drone. TheC-UAV quadcopter may include control circuits configured to receiveoutputs of the plurality of strain gauges and outputs of the one or morecameras and to adjust flying parameters of the C-UAV quadcopter inresponse to the outputs.

Forward Dynamic Mount Configuration

While the above Figures illustrate an example of a net assembly that ismounted above a UAV (at a level above the chassis and propellers of theUAV), other configurations are possible. In some examples, a netassembly may be attached to a UAV so that it is at about the same levelas the chassis and/or propellers and is laterally displaced from the UAV(e.g. in front or to one side).

FIG. 9A shows a top-down view of a UAV chassis 930 (additional UAVcomponents including propellers are omitted for clarity) with netassembly 932 mounted in front of UAV chassis 930, i.e. ahead of UAVchassis 930 along the primary direction of travel. While a UAV such as aquadcopter may be capable of travelling in different directions and doesnot always have the same orientation, a particular orientation may begenerally used, or preferred, so that when using this orientation,moving along the primary direction of travel, the net assembly extendsahead of the UAV and thus physically contacts any object (e.g. a targetdrone) before the UAV.

FIG. 9A shows UAV chassis 930 formed of four arms 930 a-d that form across (form an X-shape in cross section along the horizontal planeillustrated) with a central portion 930 e in the center of the cross.Four motors with respective propellers may be attached to arms 930 a-das previously shown in FIG. 7B (not shown in FIG. 9A for clarity) andother UAV components may be configured as described in any of theprevious examples. A rod 934 (or axle) extends between ends of first arm930 a and second arm 930 b and is attached to arms 930 a-b so that rod934 can rotate about its axis (i.e. rod 934 may be cylindrical orsubstantially cylindrical about an axis and may rotate about its axis).First bracket 936 a and second bracket 936 b attach rod 934 and netassembly 932 in a static manner (e.g. net assembly 932 rotates with rod934 and is not free to rotate separately from rod 934). In some cases,strain gauges may be attached to brackets 936 a-b or integrated withbrackets 936 a-b (and/or other components such as rod 934, frameelements of net assembly 932, arms 930 a-d, etc.) to detect impact of atarget drone with net assembly 932 and/or to provide informationregarding a target drone after it is intercepted. Rod 934 may be formedof a suitable material and with suitable dimensions so that it issomewhat flexible and may absorb shock of impact of net assembly 932and/or vibration from a target drone in net assembly 932 so that anysuch shock or vibration has a reduced effect on UAV chassis 930.

Net assembly 932 includes a net enclosure formed by a central portion932 a that extends parallel to rod 934 in the plane illustrated in FIG.9A. A first wing portion 932 b extends from the left end of centralportion 932 a and a second wing portion 932 c extends from the right endof central portion 932 a. Wing portions 932 a-b form oblique angles withcentral portion 932 a in this top-down view (e.g. 30-60 degrees). Insome cases, other angles may be formed (e.g. wings may be angled at morethan 60 degrees, at 90 degrees, or at less than 30 degrees). Straingauges 938 a-b are attached to first and second wing portionsrespectively in this example. In other examples, strain gauges may belocated at different and/or additional locations of net assembly 932. Anentanglement net 933 is attached to first and second wing portions 932a-b and extends across the opening along the front of net assembly 932.Central portion 932 a, first wing portion 932 b and second wing portion932 c may be formed of frame members of suitable material (e.g. carbonfiber, molded plastic, etc.) with enclosure netting attached to theframe members to form a net enclosure as previously described. Enclosurenetting and entanglement netting may be configured according to any ofthe examples above or otherwise. An example of suitable enclosurenetting is formed of monofilament nylon strands having a relativelylarge diameter (e.g. 1.5 mm) and may have relatively narrow spacing(e.g. ¼ inch spacing) between strands. These nylon strands may betightly strung so that there is some tension on each strand and strandsmay cross at 90 degrees to form a pattern of squares (e.g. similar to atennis racquet) or at some other angle to form a pattern of diamonds.Another example of enclosure netting uses monofilament nylon strandshaving a diameter of 0.5 mm with a spacing of 2 inches between strandsand with strands crossing at 90 degrees to form a pattern of squares, orcrossing obliquely to form a pattern of diamonds. Entanglement net 933may be formed of suitable material such as monofilament nylon strandswith a diameter of 0.5 mm and a spacing of 4 inches (e.g. wider spacingthan enclosure netting). Strands may cross at 90 degrees to form apattern of squares, may cross obliquely to form a pattern of diamonds,or may be in the form of parallel strands extending between first andsecond wing portions 923 a-b (e.g. without interweaving of strands).Entanglement net 933 may be loose (e.g. hanging down under its ownweight and with strands relaxed and hanging from frame members, e.g.attached to ends of wing portions 923 a-b.

A belt 940 extends from a motor mounted to central portion 930 e of UAVchassis 930 and is wound around a wheel attached to rod 934 so that themotor can turn rod 934 using belt 940 and thereby control rotation ofrod 934 and net assembly 932. In other examples, a driveshaft, chain, orother component may be used to transmit torque from a motor to a rod oraxle to provide controlled rotation of a net assembly. In anotherexample, a pneumatic actuator or other actuator may be used to rotatenet assembly 932.

UAV chassis 930 and net assembly 932 are further illustrated in FIG. 9B,which shows a side-on view with the plane of UAV chassis 930 horizontal(e.g. UAV at rest on a horizontal surface). FIG. 9B shows that theenclosure formed by central portion 932 a, first wing portion 932 b andsecond wing portion 932 c is crescent shaped in cross section so that ithas an opening that faces outward from UAV chassis 930 (e.g. is curvedso that the concave side of the curve faces away from UAV chassis 930).FIG. 9B also shows motor 942 (e.g. stepper motor, servo motor, or othersuitable electric motor that may be controlled by control circuits of aUAV), which drives belt 940. Belt 940 is wound about wheel 944, which isstatically (fixedly) attached to rod 934 so that turning wheel 944causes rod 934 to turn. It will be understood that wheel 944 isconcentric with rod 934 and its larger diameter allows motor 942 to moreeasily turn rod 934 than if belt 940 were directly wound about rod 934(an alternative arrangement, which may also be used). Motor 942 may becontrolled by control circuits of a UAV so that the angle of netassembly 932 with respect to UAV chassis 930 may be controlled andchanged during flight (or on the ground). In the view of FIG. 9B, theopening of net assembly 932 faces right (the primary direction of travelin this example) and faces substantially horizontally. This angle may bechanged by control circuits controlling motor 942. While not shown inFIG. 9B, net assembly 932 may include a quick release mechanism allowingrapid attachment/detachment from UAV chassis 930.

FIG. 9C shows a more detailed view of certain components of the rotationmechanism that orients net assembly 932 including rod 934, wheel 944,belt 940, and wheel 946, which may be attached to motor 942, e.g.attached directly to rotor of an electric motor so that wheel 946 turnswith the rotor. As illustrated in FIG. 9C, wheel 944 and wheel 946 mayhave cogs (or teeth) that engage corresponding features of belt 940 toprovide traction and prevent slippage when motor 942 rotates. In otherexamples, a chain, driveshaft or other component may be used to transmittorque from motor 942 to net assembly 932.

FIG. 9D shows a perspective view (from above right and from behind UAVchassis 930) including net assembly 932, with entanglement net 933extending across the outward facing opening of net assembly 932 (facingforward along the primary direction of travel). Strain gauges 938 a-bare shown attached to first and second wing portions 932 b, 932 crespectively and additional strain gauges may be attached at otherlocations (e.g. brackets 936 a-b). Rod 934, which connects UAV chassis930 and net assembly 932 is shown extending parallel to the plane of UAVchassis 930 to allow net assembly 932 to rotate and change its anglewith respect to UAV chassis 930. Also shown in FIG. 9D is camera 948,which is attached to a frame member of net assembly 932 so that it isdirected forward along the primary direction of travel and may be usedto facilitate FPV flying. More than one camera may be mounted to netassembly 932 including paired cameras forming stereoscopic cameras thatmay be used by CV circuits. Strain gauges such as strain gauges 938 a-b,cameras such as camera 796, and other sensors (e.g. optical sensors) maydetect interception of a target drone and/or may provide signals used todetermine information regarding the target drone that may be used tomodify flying parameters of a C-UAV according to the information.

FIGS. 9E-F illustrate an example of a method of operation that includesrotating net assembly 932 about the axis of rod 934 to maintain adesired orientation of net assembly 932. FIG. 9E shows motor 942attached to UAV chassis 930 so that it can drive belt 940 and thusrotate wheel 944 and thereby rotate net assembly 932. FIG. 9E shows UAVchassis 930 with its plane extending horizontally (e.g. when legs 950a-b are on a level surface or when hovering). Net assembly 932 may beconsidered to be aligned with the plane of UAV chassis 930 in this viewbecause the opening of net assembly 932 (opening where entanglement net933 extends) is facing horizontally outward from UAV chassis 930.Entanglement net 933 may be substantially vertical in thisconfiguration. In some cases, this may be a default position for netassembly 932. At certain times net assembly 932 may be rotated from thisposition, e.g. to facilitate interception of a target drone and itscapture in net assembly 932. For example, during flight, a drone may flywith a negative angle of pitch (e.g. in a nose-down orientation) so thatthrust propels the drone forwards as well as upwards. In some cases, netassembly 932 may be rotated to counteract the angle of pitch andmaintain the orientation of net assembly 932 so that its opening remainsfacing substantially horizontally.

FIG. 9F shows UAV chassis 930 having a negative angle of pitch 954 (e.g.during flight towards the right, along its primary direction of travel).In order to compensate for this negative pitch and maintain net assembly932 in a desired orientation, net assembly 932 may be rotated upwardsthrough an angle equal to the angle of pitch 954 (e.g. if angle of pitch954 is minus 20 degrees then net assembly 932 may be raised upwards by20 degrees with respect to the plane of UAV chassis 930). In this way,the opening of net assembly 932 faces along the primary direction oftravel with entanglement net 933 substantially vertical as in FIG. 9Eand thus may be aligned for interception of a target drone.

In other examples, it may be desirable to rotate net assembly 932through a different angle. For example, FIG. 9G shows net assembly 932angled upwards by an angle that is greater than angle of pitch 954 sothat the opening of net assembly 932 where entanglement net 933 extendsfaces upwards. This may allow interception of a target drone in a mannerthat scoops the target drone into net assembly 932 and reduces the riskof the target drone (or fragments of the target drone) dropping. Thisconfiguration may also facilitate approaching a drone from anon-horizontal angle (e.g. a C-UAV drone may approach a drone at anangle from below or above and net assembly 932 may be rotatedaccordingly).

In addition to facilitating interception of a target drone, rotation ofnet assembly 932 may be used during and after interception to facilitatemaintaining a captured target drone in place. FIG. 9H illustrates anexample of target drone 103 captured in net assembly 932 (e.g. entangledin entanglement net 933. Net assembly 932 is angled upwards in thisexample so that it opens upwards and thus extends below target drone103. This may reduce the risk that target drone 103 falls (or that anyfragments fall) and thereby improve safety. When interception of atarget drone is detected (e.g. from signals produced by one or morestrain gauge, camera, optical sensor, or other sensor) control circuitsmay cause motor 942 to increase the angle of tilt of net assembly 932 asillustrated so that a target drone is securely held. While this exampleshows a rotating net assembly, a static net assembly may be similarlymounted to the front of a UAV, e.g. the rotation mechanism may beomitted in some examples.

FIG. 10 illustrates a method that may be implemented using a C-UAV dronethat has a rotatable net assembly (e.g. net assembly 932). The methodincludes piloting the C-UAV drone with a net assembly towards the targetdrone 1000, rotating the net assembly with respect to the C-UAV drone(e.g. using a motor attached to the C-UAV chassis) to align the netassembly with the target drone while the C-UAV is flying towards thetarget drone 1002 (e.g. to counteract negative pitch of the C-UAV) andintercepting the target drone with the net assembly 1004 (e.g.entangling the target drone in an entanglement net). The method furtherincludes detecting interception of the target drone by one or more of astrain gauge, a camera, or an optical sensor 1006, determininginformation regarding the target drone from signals from the one or moreof a strain gauge, a camera, or an optical sensor 1008, and modifyingflying parameters of the C-UAV drone according to the informationregarding the target drone 1010.

An example of a drone includes: a drone chassis extending along a plane;a plurality of motors attached to the drone chassis; a plurality ofpropellers coupled to the plurality of motors; and a net assemblymounted to the drone chassis, the net assembly including: a netenclosure rotatably mounted such that an outward facing opening of theenclosure is rotatable about an axis of rotation that is parallel to thedrone chassis.

The drone may include a rotation mechanism configured to rotate the netenclosure with respect to the plane of the drone chassis. The rotationmechanism may include: a rod extending between arms of the dronechassis, the rod is statically attached to the net enclosure androtatably attached to the drone chassis; and a motor coupled to the rodto control rotation of the rod and net enclosure with respect to thedrone chassis. The motor may be mounted in a central portion of thedrone chassis and may be coupled to the rod by a belt extending about awheel that is attached to and concentric with the rod. The enclosure maybe mounted laterally with respect to the drone chassis such that theplane of the drone chassis extends through the enclosure. The outwardfacing opening of the enclosure may be oriented along a primarydirection of travel of the drone. The enclosure may include: a centralportion that extends parallel to the axis of rotation between a firstend and a second end and is substantially crescent shaped in crosssection along a plane perpendicular to the axis of rotation; and firstand second wing portions that extend outward from the first end and thesecond end of the central portion at an oblique angle to the centralportion. The central portion and the first and second wing portions mayinclude a frame and enclosure netting attached to the frame. The netassembly may include an entanglement net attached to the first andsecond wing portions, the entanglement net extending across the outwardfacing opening. The enclosure netting may be formed of strands ofmonofilament nylon having a first spacing and first tension and theentanglement net may be formed of strands of monofilament nylon havingsecond a spacing that is greater than the first spacing and secondtension that is less than the first tension.

An example of a method of intercepting a target drone with acounter-unmanned aerial vehicle (C-UAV) drone includes: piloting theC-UAV drone with a net assembly towards the target drone; rotating thenet assembly with respect to the C-UAV drone to align the net assemblywith the target drone while the C-UAV is flying towards the targetdrone; and intercepting the target drone with the net assembly.

When the C-UAV is flying towards the target drone it may have a negativepitch and rotating the net assembly according to the method may at leastpartially counteract the negative pitch of the C-UAV. The net assemblymay include an opening along a primary direction of travel of the C-UAVand intercepting the target drone may include aligning the opening withthe target drone while the C-UAV is flying such that the target droneenters the opening. The net assembly may include an entanglement netextending across the opening and intercepting the target drone mayinclude entangling the target drone in the entanglement net. The C-UAVmay include a chassis extending along a plane and rotating the netassembly with respect to the C-UAV may include using a motor attached tothe chassis to rotate the net assembly about an axis of rotation thatextends parallel to the plane. The method may further include: detectinginterception of the target drone by one or more of a strain gauge, acamera, or an optical sensor; determining information regarding thetarget drone from signals from the one or more of a strain gauge, acamera, or an optical sensor; and modifying flying parameters of theC-UAV drone according to the information regarding the target drone.

An example of a Counter-Unmanned Aerial Vehicle (C-UAV) quadcopterincludes: a quadcopter chassis extending along a plane, the quadcopterchassis having a first arm, a second arm, a third arm, and a fourth armforming an X-shape in cross section along the plane; a first motor, asecond motor, a third motor, and a fourth motor respectively attached tothe first, second, third, and fourth arms of the quadcopter chassis; afirst propeller, a second propeller, a third propeller, and a fourthpropeller coupled to the respective first, second, third, and fourthmotors; a net assembly rotatably attached to ends of the first andsecond arms of the quadcopter chassis; and a motor attached to thequadcopter chassis, the motor coupled to the net assembly to rotate thenet assembly with respect to the plane of the quadcopter chassis.

The net assembly may include: a central portion that extends parallel toan axis of rotation of the net assembly between a first end and a secondend and is substantially crescent shaped in cross section along a planeperpendicular to the axis of rotation; first and second wing portionsthat extend outward from the first and second ends of the centralportion at an oblique angle to the central portion; and an entanglementnet attached to the first and second wing portions, the entanglement netextending parallel to the central portion and in front of the centralportion along a primary direction of travel of the C-UAV. The C-UAVquadcopter may include: one or more strain gauges or optical sensorsattached to components of the net assembly to detect presence of atarget drone in the net assembly; one or more cameras mounted to the netassembly for First Person View (FPV) operation of the C-UAV forintercepting the target drone; and control circuits configured toreceive outputs of the one or more strain gauges or optical sensors andoutputs of the one or more cameras and to adjust flying parameters ofthe C-UAV quadcopter in response to the outputs. The control circuitsmay be further configured to determine pitch of the C-UAV and controlthe motor to rotate the net assembly to counteract the pitch such thatthe net assembly is substantially aligned for interception of a targetdrone.

Collapsible Top-Mount Configuration

FIG. 11A shows shows an example of a top-mounted net assembly 1120 thatmay be mounted to a UAV (e.g. UAV 710 as shown here, or another UAV suchas any of the UAVs previously discussed) that may be configured forC-UAV operation so that it extends above propellers of the UAV (e.g. ina manner similar to net assembly 722 and net assembly 802). Net assembly1120 includes a bottom portion 1120 a (floor) that is similar to bottomportions 772 a and 802 a as previously shown and may include framemembers forming a square with cross bars between corners of the squarein an X configuration (e.g. as shown in FIG. 7B). One or more straingauges may be attached to cross bars of bottom portion 1120 a (e.g. asillustrated in FIG. 7F) and/or other frame members of net assembly 1120.Bottom portion 1120 a may be similarly aligned with a UAV and may besimilarly attached using a dampener 1129 (e.g. like dampener 786),elastic elements 1125 a-b (e.g. similar to elastic elements 790 a-b),and a quick release component 1127 (similar to quick release component784) coupling net assembly 1120 to chassis 712 of UAV 710 as illustratedin FIGS. 7H-I. Net assembly 1120 is generally symmetric from front toback and from side to side so that (unlike net assembly 722) the front,back, and side portions are similar in size and shape. Thus, while FIG.11A shows net assembly 1120 and UAV 710 from the front, these may looksimilar in side-view or from the rear. While UAV 710 includes lowerpropellers 714 a-b in addition to propellers over quadcopter chassis 712(and includes legs 716 a-b to provide clearance) net assembly 1120 maybe used with a wide variety of UAVs and the example shown here is forillustration only (e.g. different quadcopters, drones, UAVs may beequipped with net assembly 1120).

In addition to bottom portion 1120 a, net assembly 1120 includes frontportion 1120 b, which extends between first upright frame member 1122 aand second upright frame member 1122 b. Front portion 1120 b may beattached to the tops of first and second upright frame members 1122 a-band may also be attached to bottom portion 1120 a at locations inboardof where first and second upright frame members 1122 a-b attach tobottom portion 1120 a by means of articulating joints 1124 a and 1124 brespectively. Articulating joints 1124 a-b (e.g. hinges, flexiblecouplings, or other articulating joints) allow upright frame members toarticulate inwards by rotating (inwards towards the central axis of netassembly 1120, which extends vertically from the center of bottomportion 1120 a) from the open position shown (forming an angle ofapproximately 120 degrees with respect to bottom portion 1120 a) to aclosed position (e.g. less than 90 degrees, for example, 30 degrees orless). To provide force to move upright frame members 1122 a-b, one ormore elastic components may be provided in net assembly 1120. Forexample, FIG. 11A shows elastic components 1126 a and 1126 b extendingalong edges of front portion 1120 b such that they exert force onupright frame members 1122 a-b that can help to pull upright framemembers 1122 a-b inwards. In addition, elastic component 1126 c extendsalong the top of front portion 1120 b and also exerts force on tops ofupright frame members 1122 a-b that tends to pull them inwards (i.e.tends to rotate them about articulating joints 1124 a-b so that theyconverge.

FIG. 11B illustrates net assembly 1120 in a closed position with uprightframe members inclined inwards (approximately 30 degrees from bottomportion 1120 a). Articulating joints 1124 a-b allow upright framemembers 1122 a-b to articulate between the open position of FIG. 11A tothe closed position of FIG. 11B and elastic components (or othercomponents such as springs, magnets, pneumatic actuators,electromechanical actuators, or other actuating mechanisms) provideforce to move upright frame members 1122 a-b and thus move front portion1120 b. In addition, side and back portions may be similarly movedbetween positions so that an enclosure that is formed by front, back,and side portions may have a relatively large top opening in the openposition and this opening may be reduced in the closed position. In thisway, a target drone may be captured within such an enclosure, therebypreventing escape of the target drone and/or portions of the drone (e.g.fragments resulting from collision).

Changing from the open position to the closed position may be triggeredby a triggering event such as detection of a target drone in, or inclose proximity to net assembly 1120. Components such as one or morecamera, one or more strain gauge, one or more sensor, or other componentmay provide signals that are used to detect the presence of a drone inproximity to net assembly 1120 (e.g. in a position where closing netassembly 1120 results in capture of the target drone).

One or more camera may be mounted to net assembly 1120. For example,FIGS. 11A-B show camera 1128 attached to the center of bottom portion1120 a (e.g. where cross beams intersect). Alternatively oradditionally, cameras may be placed at other locations on net assembly1120 and/or quadcopter 710. In some cases, pairs of cameras are used toform stereoscopic cameras (e.g. for use with CV and AI control asdescribed above). Camera 1128 may be used to fly drone 710 (e.g.providing FPV ability) and/or may be used to detect interception of atarget drone.

One or more strain gauge may be mounted to net assembly 1120. Forexample, strain gauges may be attached to cross beams of bottom portion1120 a (e.g. as shown in FIG. 7F). In an example, strain gauges may beintegrated with articulating joints such as articulating joints 1124 a-bso that when force is applied on an upright frame member, a strain gaugedetects the force, which may be used as an indicator that a target dronehas been intercepted. It will be understood that (in this and other netassembly configurations) an output from a single strain gauge may besufficient to indicate interception of a target drone in some cases. Insome cases, outputs from multiple strain gauges may be combined toindicate interception of a target drone. For example, strain gauges maybe averaged, more than a predetermined number of strain gauges may reacha threshold output to indicate interception, differences between straingauge outputs may be used, or strain gauge outputs may be combined insome other way. Strain gauge outputs may be combined with one or morecamera output and/or sensor output so that detection of interception maybe based on multiple outputs using one or more different technologies.

Sensors, such as optical sensors may be used to detect a target drone.For example, an optical beam may extend across net assembly 1120 so thatinterruption of the beam indicates interception of a target drone. Inother examples, reflection of a beam (optical, radar, lidar, sonic orother beam) from a target drone may be used to detect interception.

FIGS. 11C-D provide further illustration of net assembly 1120 in theopen and closed positions respectively showing additional portions ofnet assembly 1120 that were not visible in FIGS. 11A-B. In addition tofirst and second upright frame members 1122 a-b shown in FIGS. 11A-B,FIGS. 11C-D show third upright frame member 1122 c and fourth uprightframe member 1122 d coupled to bottom portion 1120 a by articulatingjoints 1124 c and 1124 d respectively so that these too are articulatingupright frame members. Each articulating joint 1124 a-d allows itscorresponding upright frame member to rotate inwards. Also shown inFIGS. 11C-D are a first side portion 1120 c extending between the secondupright frame member 1122 b and third upright frame member 1122 c, aback portion 1120 d extending between the third upright frame member1122 c and fourth upright frame member 1122 d, and a second side portion1120 e extending between the fourth upright frame member 1122 d and thefirst upright frame member 1122 a. Elastic components extend along thetops of these portions. In addition to elastic component 1126 c, whichextends along the upper edge of front portion 1120 b, elastic component1126 d extends along the top of first side portion 1120 c, elasticcomponent 1126 e extends along the top of back portion 1120 d, andelastic component 1126 f extends along the top of second side portion1120 e. Elastic components 1126 c-f define an opening that extendsacross the top of net assembly 1120, which allows entry of a targetdrone into the enclosure formed by net assembly 1120. Elastic components1126 c-f (in combination with elastic components 1126 a-b and similarelastic components attached to third and fourth upright frame members1122 c-d, which are not visible in this view) pull upright frame members1122 inwards to transition net assembly 1120 from the open position tothe closed position. While no netting extends across the top of netassembly 1120 in this example, in some cases, entanglement netting mayextend across the top of net assembly 1120 similarly to entanglement net972 (and with such entanglement netting, net assembly 1120 may beoperated in a static mode, without rotating any frame members, similarlyto net assembly 772).

FIG. 11D shows net assembly 1120 in the closed position from the sameperspective as shown in FIG. 11A. It can be seen that upright framemembers 1122 a-d have rotated inwards so that their tops are closetogether (closer than in the open position and in this example, close totouching). The opening along the tops of portions 1120 b-e is reducedfrom an opening having a first size (larger than bottom portion 1120 aand larger than quadcopter 710, e.g. more than two feet wide) thatallows a target drone to enter to a smaller second size that does notallow a target drone (or significant parts thereof) to exit (e.g. lessthan six inches wide).

FIGS. 11E-F provide further illustration of net assembly 1120 intop-down view in the open and closed positions respectively.Articulating joints 1124 a-d allow corresponding upright frame members1122 a-d to rotate inwards. Also shown in FIGS. 11E-F are front portion1120 b extending between first upright frame member 1122 a and secondupright frame member 1122 b, first side portion 1120 c extending betweenthe second upright frame member 1122 b and third upright frame member1122 c, back portion 1120 d extending between the third upright framemember 1122 c and fourth upright frame member 1122 d, and a second sideportion 1120 e extending between the fourth upright frame member 1122 dand the first upright frame member 1122 a. Elastic components 1126 c-fextend along the tops of these portions. Elastic component 1126 cextends along the upper edge of front portion 1120 b, elastic component1126 d extends along the top of first side portion 1120 c, elasticcomponent 1126 e extends along the top of back portion 1120 d, andelastic component 1126 f extends along the top of second side portion1120 e. Elastic components 1126 c-f define an opening that extendsacross the top of net assembly 1120 (opening facing up in this top-downview) and pull upright frame members 1122 a-d inwards to transition netassembly 1120 from the open position to the closed position.

FIG. 11F shows net assembly 1120 in the closed position from the sametop-down perspective as shown in FIG. 11E. Upright frame members 1122a-d have rotated inwards so that they overlie cross beams of bottomportion 1120 a and are not separately visible. The opening formed byelastic components 1126 c-f along the tops of portions 1120 b-e isreduced from a large opening that allows a target drone to enter to amuch smaller opening that does not allow a target drone (or significantparts thereof) to escape. Front portion 1120 b, first side portion 1120c, back portion 1120 d, and second side portion 1120 e become inclinedinwards as upright frame members 1122 a-d to which they are attachedrotate inwards. Front portion 1120 b, first side portion 1120 c, backportion 1120 d, and second side portion 1120 e extend over bottomportion 1120 a in this top-down view so that an enclosure between bottomportion 1120 a below and front portion 1120 b, first side portion 1120c, back portion 1120 d, and second side portion 1120 e above can hold atarget drone during and after interception. The shapes of front portion1120 b, first side portion 1120 c, back portion 1120 d, and second sideportion 1120 e may change during this transition from a trapezoid shapewith an upper edge longer than its lower edge to a nearly triangularshape with a very short upper edge (lower edge where it joins bottomportion 1120 a remains the same).

Appropriate material may be used for netting of bottom, front, back andside portions 1120 a-e, which are each formed of a panel of nettingextending between frame members. For example, bottom portion 1120 a maybe formed of enclosure netting while front, back, and side portions 1120b-e are formed of entanglement netting. Such enclosure netting andentanglement netting may be configured according to any of the examplesabove or otherwise. An example of suitable enclosure netting of bottomportion 1120 a is formed of monofilament nylon strands having arelatively large diameter (e.g. 1.5 mm) and may have relatively narrowspacing (e.g. ¼ inch spacing) between strands. These nylon strands maybe tightly strung so that there is some tension on each strand andstrands may cross at 90 degrees to form a pattern of squares (e.g.similar to a tennis racquet) or at some other angle to form a pattern ofdiamonds. Another example of enclosure netting uses monofilament nylonstrands having a diameter of 0.5 mm with a spacing of 2 inches betweenstrands and with strands crossing at 90 degrees to form a pattern ofsquares or crossing obliquely to form a pattern of diamonds.Entanglement netting used for front, back, and side portions 1120 b-emay be formed of suitable material such as monofilament nylon strandswith a diameter of 0.5 mm and a spacing of 4 inches (e.g. wider spacingthan enclosure netting). Strands may cross at 90 degrees to form apattern of squares, may cross obliquely to form a pattern of diamonds,or may be in the form of parallel strands extending between uprightframe members (e.g. without interweaving of strands). Entanglement netmay be loose (e.g. hanging down under its own weight and with strandsrelaxed and hanging from upright frame members. When in the closedposition or transitioning from the open position to the closed position,such entanglement netting may become looser and thus facilitateentanglement of a target drone.

Elastic components such as elastic components 1126 a-f may be formed ofany suitable elastic material such as elastic chord (e.g. shock chord)and may extend in any suitable configuration. More than one elasticcomponent may be formed from a given length of such elastic chord, e.g.a single piece of chord may extend along the tops of front, back, andside portions 1120 b-e to form elastic components 1126 c-f. Othercomponents such as springs, pneumatic actuators, electromechanicalactuators, or other actuating mechanisms may be used instead of, or incombination with elastic components to effectuate transition of a netassembly from the open position to the closed position. In general,returning a net assembly from the closed position to the open positionmay be performed manually, e.g. on the ground, to remove a target dronethat is captured. In some cases, a mechanism may be included to return anet assembly to the open position from the closed position withoutmanual intervention. Thus, a C-UAV drone with a net assembly that closeswithout capturing a target drone may return to the open position withoutlanding (i.e. may transition from the closed position to the openposition in-flight) so that the C-UAV may attempt to capture a targetdrone more than once without landing. Suitable pneumatic,electromechanical or other actuating mechanism may be provided toeffectuate such a transition, which may be performed in response to acommand from a user (via remote-control) or from control circuits of aUAV (including AI controller circuits).

Closing of net assembly 1120 (transitioning from the open position tothe closed position) may occur when a target drone is intercepted (e.g.as detected by one or more of a camera, strain gauge, or sensor) and maybe performed by any suitable components. An example of such a componentis an electromechanical actuator that may maintain an upright framemember in an open position as appropriate and may change to allow theupright frame member to rotate inwards to the closed position inresponse to command or signal.

FIGS. 11G-H show details of an example electromechanical actuator thatis used in combination with an articulating joint to facilitatetransitioning between an open position and a closed position. FIG. 11Gshows electromechanical actuator 1130 that is extended so that arm 1132extends outwards from the body of electromechanical actuator 1130 tomaintain upright frame member 1122 b in the open position. This in turnmaintains front portion 1120 b extending so that it inclines outwardsfrom the center of net assembly 1120. The end of arm 1132 has a ballthat engages with a corresponding depression in upright frame member1122 b thus physically connecting electromechanical actuator 1130 andupright frame member 1122 b. Electromechanical actuator 1130 maymaintain this position until a signal is received causingelectromechanical actuator 1130 to retract arm 1132, thereby allowingelastic component 1126 b and other elastic components to rotate the topof upright frame member 1122 b inwards about articulating joint 1124 b.

FIG. 11H shows upright frame member 1122 b in the closed position(corresponding to FIG. 11B), with arm 1132 retracted to allow elasticcomponents to pull upright frame member 1122 b inwards. It will beunderstood that all upright frame members may have similarelectromechanical actuators so that all upright frame members may rotateat the same time thereby collapsing front, back, and sides of netassembly 1120. Signals to four actuators coupled to upright framemembers 1122 a-d may be synchronized (or a common signal may be sent) sothat all upright frame members close together in response to capture ofa target drone and thereby cause upright frame members to articulateinwards.

FIGS. 11I-J illustrate an example of capture of a target drone 1160 byUAV 710 configured with net assembly 1120 (configured as a C-UAV). FIG.11I shows UAV 710 flying towards target drone 1160 so that it approachestarget drone 1160 from below. Thus, the opening at the top of netassembly 1120 faces target drone 1160. For example, camera 1128 may beused to pilot UAV 710 to align net assembly 1120 with target drone 1160during approach (e.g. provided to a user or CV circuits). Net assembly1120 is in the open position with upright frame members 1122 a, 1122 dextending outward and providing a large opening at the top of netassembly 1120 (e.g. held at this angle by electromechanical actuators).

FIG. 11J shows UAV 710 and net assembly 1120 after interception oftarget drone 1160. When camera 1128 and/or other cameras, strain gauges,sensors detect that target drone 1160 is intercepted (e.g. the presenceof the target drone is detected within the net assembly) net assembly1120 collapses to the closed position shown in FIG. 11J by rotatingupright frame members 1122 a, 1122 d (and other upright frame members)inwards to narrow the opening formed and enclose target drone 1160within the enclosure formed by the bottom, front, back, and sideportions of net assembly 1120. Entanglement of propellers of targetdrone 1160 may occur before or during inward rotation of upright framemembers, which draws netting of front, back, and side portions inwardstowards the propellers of target drone 1160. With target drone 1160captured in net assembly 1120 in this way, UAV 710 may fly to ground andnet assembly 1120 may be removed (using a quick release mechanism) withtarget drone 1160 inside.

FIG. 12 illustrates a method of intercepting a target drone with a C-UAVdrone (e.g. UAV 710 configured with net assembly 1120). The methodincludes piloting the C-UAV drone towards the target drone 1270 andorienting the C-UAV drone to align an opening of a net assembly mountedabove propellers of the C-UAV drone with the target drone while flyingtowards the target drone 1272. The method further includes detectingpresence of the target drone within the net assembly 1274 (e.g. usingoutput of one or more of a camera, a strain gauge, a sensor or otherdevice attached to net assembly 1120) and in response to detecting thepresence of the target drone within the net assembly, reducing theopening of the net assembly to capture the target drone 1276 (e.g. byproviding signals to actuators to cause upright frame members to rotateinwards). The method additionally includes subsequently piloting theC-UAV drone with the target drone to a landing point 1278 and detachingthe net assembly with the captured target drone from the C-UAV using aquick-release mechanism 1280.

FIG. 13 illustrates an example of certain components that may be used inone or more methods above. In some cases (e.g. in examples shown inFIGS. 8A-E, 9A-H, and 11A-J) one or more component may be moved by anactuator in response to detection of a target drone (e.g. detection ofcollision with a target drone, imminent collision, presence of a targetdrone within or partially within a target drone). FIG. 13 illustratescontrol circuits 1384 that include detection circuits 1386, which areconfigured to detect such a triggering event. Detection circuits 1386may be formed by dedicated circuits or may be formed by circuits thatare configured by firmware or software to perform certain functions. Forexample, detection circuits may be formed in a flight controller (e.g.flight controller 211) in an AI controller (e.g. AI controller 330) orsome other controller in a UAV. Detection circuits 1386 receive signalsfrom one or more cameras 1388, one or more strain gauges 1390, one ormore optical sensors 1392, and one or more other sensors (e.g. acousticsensors, radar, lidar) 1394, which may be attached to a net assemblyand/or UAV. Detection circuits 1386 use one or more of these signals todetermine when a target drone is intercepted. When this determination ispositive (interception is determined to have occurred) one or moreactuators 1398 are triggered (e.g. when they receive a predeterminedinput, they change to from the extended position to the retractedposition).

While this example shows cameras, strain gauges, optical sensors, andother sensors, it will be understood that these are for illustration andfewer components may be used (e.g. a single camera, strain gauge,optical or other sensor may be sufficient in some cases). Implementationcan use any combination of one or more of these components. Detectioncircuits 1386 may combine these signals in various ways so thatfalse-positive results are avoided. For example, a camera signalindicating interception may be confirmed by a strain gauge and detectionmay require both. Strain gauge readings may be averaged or otherwisecombined so that one outlier reading does not trigger actuation. Similarcombination may be applied to optical and other sensor signals. Whendetection circuits 1386 determine that interception has occurred, asignal is sent to actuator(s) 1398 to cause movement of the actuator(s)to thereby move one or more component of a net assembly (e.g. closing oflatch 806, rotation of net assembly 932, or closing of net assembly1120).

An example of a drone includes: a drone chassis; a plurality of motorsattached to the drone chassis; a plurality of propellers coupled to theplurality of motors, the plurality of propellers extending above thedrone chassis; and a net assembly mounted to the drone chassis, the netassembly extending above the plurality of propellers, the net assemblyincluding a bottom portion and a plurality of upright frame members thatare mounted to the bottom portion by a plurality of articulating joints.

The bottom portion may be substantially square, the plurality of uprightframe members may include an upright frame member mounted at each cornerof the bottom portion, a front portion of the net assembly extendingbetween a first upright frame member and a second upright frame member,a first side portion extending between the second upright frame memberand a third upright frame member, a back portion extending between thethird upright frame member and a fourth upright frame member, and asecond side portion extending between the fourth upright frame memberand the first upright frame member. The drone may include elasticcomponents attached to the plurality of upright frame members to movethe plurality of upright frame members from an open position thatmaintains an opening between upper edges of the front portion, firstside portion, back portion, and second side portion at a first size to aclosed position that reduces the opening to a second size that is lessthan the first size. The drone may include a plurality of actuatingmechanisms configured to maintain the plurality of upright frame membersin the open position and in response to a predetermined input cause theplurality of upright frame members to articulate inwards. The drone mayinclude one or more camera or strain gauge, wherein the predeterminedinput to cause the plurality of upright frame members to articulateinwards is generated in response to outputs from one or more camera orstrain gauge. The bottom portion may include netting formed ofmonofilament nylon strands of a first diameter having a first spacing,the front portion, the first side portion, the back portion, and thesecond side portion may include netting formed of monofilament nylonstrands of a second diameter that is less than the first diameter andhave a second spacing that is greater than the first spacing. The dronemay include a quick-release mechanism coupling the net assembly to thedrone chassis. The drone may include one or more strain gauges attachedto the plurality of articulating joints to measure strain and detectinterception of a target drone in the net assembly. The drone mayinclude a dampener coupled between the net assembly and the dronechassis and one or more elastic components coupled between the netassembly and the drone chassis to reduce transmission of vibration fromthe net assembly to the drone chassis.

An example of a method of intercepting a target drone with acounter-unmanned aerial vehicle (C-UAV) drone includes piloting theC-UAV drone towards the target drone; orienting the C-UAV drone to alignan opening of a net assembly mounted above propellers of the C-UAV dronewith the target drone while flying towards the target drone; detectingpresence of the target drone within the net assembly; and in response todetecting the presence of the target drone within the net assembly,reducing the opening of the net assembly to capture the target drone.

Detecting the presence of the target drone within the net assembly mayinclude receiving output from one or more of a camera, a strain gauge,or a sensor attached to the net assembly. Reducing the opening of thenet assembly may include providing signals to a plurality of actuatorsthat are physically connected to upright frame members of the netassembly to cause the upright frame members to rotate inwards towards acentral axis of the net assembly. The net assembly may include a bottomportion extending over propellers of the C-UAV drone and a frontportion, a back portion, and side portions extending upwards from edgesof the bottom portion to form an enclosure and reducing the opening ofthe net assembly may include inclining the front portion, back portionand side portions inwards to reduce the size of the enclosure.

The method may include subsequently piloting the C-UAV drone with thetarget drone to a landing point; and detaching the net assembly with thecaptured target drone from the C-UAV using a quick-release mechanism.The net assembly may include a camera and orienting the C-UAV drone toalign the net assembly with the target drone may include using aFirst-Person View (FPV) provided by the camera.

An example of a Counter-Unmanned Aerial Vehicle (C-UAV) quadcopterincludes: a quadcopter chassis; a first motor, a second motor, a thirdmotor, and a fourth motor attached to the quadcopter chassis; a firstpropeller, a second propeller, a third propeller, and a fourth propellercoupled to the respective first, second, third, and fourth motors abovethe quadcopter chassis; and a net assembly mounted to the quadcopterchassis, the net assembly extending above the first, second, third, andfourth propellers, the net assembly including: a plurality ofarticulating upright frame members configured to spread outward in anopen position and to collapse inward in a closed position; one or moreof a strain gauge, a camera, or a sensor configured to detect presenceof a target drone in the net assembly; and one or more actuatorsconfigured to cause the plurality of articulating upright frame membersto transition from the open position to the closed position in responseto detection of the presence of the target drone in the net assembly.

The C-UAV quadcopter may include control circuits configured to receiveoutputs of the one or more of a strain gauge, a camera, or a sensor andto adjust flying parameters of the C-UAV quadcopter in response to theoutputs. The C-UAV quadcopter may include a plurality of elasticcomponents physically connected to the plurality of articulating uprightframe members to apply force to the plurality of articulating uprightframe members to move the plurality of articulating upright framemembers from the open position to the closed position. The C-UAVquadcopter may include a quick-release mechanism coupling the netassembly to the quadcopter chassis. The C-UAV quadcopter may include adampener coupled between the net assembly and the quadcopter chassis andone or more elastic elements coupled between the net assembly and thequadcopter chassis to reduce transmission of vibration from the netassembly to the quadcopter chassis.

For purposes of this document, it should be noted that while variousexamples are given with specific combinations of components and specificconfigurations, in general, components used in one example may also beused in other examples and configurations may be combined. Thus, forexample different net assemblies may be combined with a single C-UAVdrone. Components from one example or a net assembly above may becombined with components of another example, e.g. a rotation mechanismmay be added to any of the net assemblies above and any of the camera,strain gauge, optical sensor or other sensor configurations shown may beused with any of the net assemblies.

For purposes of this document, it should be noted that the dimensions ofthe various features depicted in the figures may not necessarily bedrawn to scale.

For purposes of this document, reference in the specification to “anembodiment,” “one embodiment,” “some embodiments,” or “anotherembodiment” may be used to describe different embodiments or the sameembodiment.

For purposes of this document, a connection may be a direct connectionor an indirect connection (e.g., via one or more other parts). In somecases, when an element is referred to as being connected or coupled toanother element, the element may be directly connected to the otherelement or indirectly connected to the other element via interveningelements. When an element is referred to as being directly connected toanother element, then there are no intervening elements between theelement and the other element. Two devices are “in communication” ifthey are directly or indirectly connected so that they can communicateelectronic signals between them.

For purposes of this document, the term “based on” may be read as “basedat least in part on.”

For purposes of this document, without additional context, use ofnumerical terms such as a “first” object, a “second” object, and a“third” object may not imply an ordering of objects, but may instead beused for identification purposes to identify different objects.

For purposes of this document, the term “set” of objects may refer to a“set” of one or more of the objects.

The foregoing detailed description has been presented for purposes ofillustration and description. It is not intended to be exhaustive or tolimit to the precise form disclosed. Many modifications and variationsare possible in light of the above teaching. The described embodimentswere chosen in order to best explain the principles of the proposedtechnology and its practical application, to thereby enable othersskilled in the art to best utilize it in various embodiments and withvarious modifications as are suited to the particular use contemplated.It is intended that the scope be defined by the claims appended hereto.

1. A drone comprising: a drone chassis; a plurality of motors attachedto the drone chassis; a plurality of propellers coupled to the pluralityof motors, the plurality of propellers extending above the dronechassis; and a net assembly mounted to the drone chassis, the netassembly extending above the plurality of propellers, the net assemblyincluding a bottom portion and a plurality of upright frame members thatare mounted to the bottom portion by a plurality of articulating joints.2. The drone of claim 1 wherein the bottom portion is substantiallysquare, the plurality of upright frame members include an upright framemember mounted at each corner of the bottom portion, a front portion ofthe net assembly extending between a first upright frame member and asecond upright frame member, a first side portion extending between thesecond upright frame member and a third upright frame member, a backportion extending between the third upright frame member and a fourthupright frame member, and a second side portion extending between thefourth upright frame member and the first upright frame member.
 3. Thedrone of claim 2 further including elastic components attached to theplurality of upright frame members to move the plurality of uprightframe members from an open position that maintains an opening betweenupper edges of the front portion, first side portion, back portion, andsecond side portion at a first size to a closed position that reducesthe opening to a second size that is less than the first size.
 4. Thedrone of claim 3 further comprising a plurality of actuating mechanismsconfigured to maintain the plurality of upright frame members in theopen position and in response to a predetermined input cause theplurality of upright frame members to articulate inwards.
 5. The droneof claim 4 further comprising one or more camera or strain gauge,wherein the predetermined input to cause the plurality of upright framemembers to articulate inwards is generated in response to outputs fromone or more camera or strain gauge.
 6. The drone of claim 2 wherein thebottom portion includes netting formed of monofilament nylon strands ofa first diameter having a first spacing, the front portion, the firstside portion, the back portion, and the second side portion includenetting formed of monofilament nylon strands of a second diameter thatis less than the first diameter and have a second spacing that isgreater than the first spacing.
 7. The drone of claim 1 furthercomprising a quick-release mechanism coupling the net assembly to thedrone chassis.
 8. The drone of claim 1 further comprising one or morestrain gauges attached to the plurality of articulating joints tomeasure strain and detect interception of a target drone in the netassembly.
 9. The drone of claim 1 further comprising a dampener coupledbetween the net assembly and the drone chassis and one or more elasticcomponents coupled between the net assembly and the drone chassis toreduce transmission of vibration from the net assembly to the dronechassis.
 10. A method of intercepting a target drone with acounter-unmanned aerial vehicle (C-UAV) drone comprising: piloting theC-UAV drone towards the target drone; orienting the C-UAV drone to alignan opening of a net assembly mounted above propellers of the C-UAV dronewith the target drone while flying towards the target drone; detectingpresence of the target drone within the net assembly; and in response todetecting the presence of the target drone within the net assembly,reducing the opening of the net assembly to capture the target drone.11. The method of claim 10 wherein detecting the presence of the targetdrone within the net assembly includes receiving output from one or moreof a camera, a strain gauge, or a sensor attached to the net assembly.12. The method of claim 10 wherein reducing the opening of the netassembly includes providing signals to a plurality of actuators that arephysically connected to upright frame members of the net assembly tocause the upright frame members to rotate inwards towards a central axisof the net assembly.
 13. The method of claim 10 wherein the net assemblyincludes a bottom portion extending over propellers of the C-UAV droneand a front portion, a back portion, and side portions extending upwardsfrom edges of the bottom portion to form an enclosure and whereinreducing the opening of the net assembly includes inclining the frontportion, back portion and side portions inwards to reduce the size ofthe enclosure.
 14. The method of claim 10 further comprising:subsequently piloting the C-UAV drone with the target drone to a landingpoint; and detaching the net assembly with the captured target dronefrom the C-UAV using a quick-release mechanism.
 15. The method of claim10 wherein the net assembly includes a camera and orienting the C-UAVdrone to align the net assembly with the target drone includes using aFirst Person View (FPV) provided by the camera.
 16. A Counter-UnmannedAerial Vehicle (C-UAV) quadcopter comprising: a quadcopter chassis; afirst motor, a second motor, a third motor, and a fourth motor attachedto the quadcopter chassis; a first propeller, a second propeller, athird propeller, and a fourth propeller coupled to the respective first,second, third, and fourth motors above the quadcopter chassis; and a netassembly mounted to the quadcopter chassis, the net assembly extendingabove the first, second, third, and fourth propellers, the net assemblyincluding: a plurality of articulating upright frame members configuredto spread outward in an open position and to collapse inward in a closedposition; one or more of a strain gauge, a camera, or a sensorconfigured to detect presence of a target drone in the net assembly; andone or more actuators configured to cause the plurality of articulatingupright frame members to transition from the open position to the closedposition in response to detection of the presence of the target drone inthe net assembly.
 17. The C-UAV quadcopter of claim 16 furthercomprising control circuits configured to receive outputs of the one ormore of a strain gauge, a camera, or a sensor and to adjust flyingparameters of the C-UAV quadcopter in response to the outputs.
 18. TheC-UAV quadcopter of claim 16 further comprising a plurality of elasticcomponents physically connected to the plurality of articulating uprightframe members to apply force to the plurality of articulating uprightframe members to move the plurality of articulating upright framemembers from the open position to the closed position.
 19. The C-UAVquadcopter of claim 16 further comprising a quick-release mechanismcoupling the net assembly to the quadcopter chassis.
 20. The C-UAVquadcopter of claim 16 further comprising a dampener coupled between thenet assembly and the quadcopter chassis and one or more elastic elementscoupled between the net assembly and the quadcopter chassis to reducetransmission of vibration from the net assembly to the quadcopterchassis.